VSA

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2005

2005-08 BRAK-08 BRAK ESES VS

VSA (VA (Vehicle Stabilitehicle Stabilit y Assiy Assi st) System Componst) System Compon ents - Rents - RLL

COMPONENT LOCATION INDEX

Fig. 1: Identifying VSA System Components Location Fig. 1: Identifying VSA System Components Location Courtesy of AMERICAN HONDA MOTOR CO., INC. Courtesy of AMERICAN HONDA MOTOR CO., INC.

GENER

GENERA

AL

L TROUBL

TROUBLESHOO

ESHOOTING INFO

TING INFORMATION

RMATION

SYSTEM INDICATOR SYSTEM INDICATOR

This system has four indicators: ABS indicator (A), VSA indicator (B), VSA activation indicator (C) and This system has four indicators: ABS indicator (A), VSA indicator (B), VSA activation indicator (C) and brake system indicator (D). When the system detects a problem, it illuminates the appropriate indicators. brake system indicator (D). When the system detects a problem, it illuminates the appropriate indicators.

Depending on the failure, the control unit determines which indicators are turned on. Depending on the failure, the control unit determines which indicators are turned on.



 When ABS function is lost:When ABS function is lost:

ABS indicator, VSA indicator, and VSA activation indicators turn on. ABS indicator, VSA indicator, and VSA activation indicators turn on.



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VSA indicator and VSA activation indicators turn on. VSA indicator and VSA activation indicators turn on.

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 When all functions are lost:When all functions are lost:

All four indicators turn on. All four indicators turn on.

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 When the gauge control module detects F-CAN circuit problem:When the gauge control module detects F-CAN circuit problem:

VSA indicator and brake system indicators turn on. VSA indicator and brake system indicators turn on.

Fig. 2: Identifying ABS Indicator, VSA Indicator And VSA Activation Indicator Fig. 2: Identifying ABS Indicator, VSA Indicator And VSA Activation Indicator Courtesy of AMERICAN HONDA MOTOR CO., INC.

Courtesy of AMERICAN HONDA MOTOR CO., INC. ABS/VSA INDICATOR

ABS/VSA INDICATOR

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 If the system is OK, the ABS and VSA indicators will go off 2 seconds after turning the ignitionIf the system is OK, the ABS and VSA indicators will go off 2 seconds after turning the ignition

switch ON (II). switch ON (II).



 The ABS and VSA indicators come on when the control unit detects a problem in the system.The ABS and VSA indicators come on when the control unit detects a problem in the system.

However, even though the system is operating properly, the activation indicator may come on under However, even though the system is operating properly, the activation indicator may come on under these conditions:

these conditions:



 One drive wheel is stuck.One drive wheel is stuck. 

 The vehicle goes into a spin.The vehicle goes into a spin. 

 The ABS or VSA continues to operate for a long time.The ABS or VSA continues to operate for a long time. 

 The vehicle is subjected to an electrical signal disturbance.The vehicle is subjected to an electrical signal disturbance. 

 The VSA switch has been manually turned off.The VSA switch has been manually turned off. 

 When an abnormality in the TPMS (Tire Pressure Monitoring System) or low tire pressure isWhen an abnormality in the TPMS (Tire Pressure Monitoring System) or low tire pressure is

detected, VSA functions cannot be cancelled by pressing the VSA OFF switch. detected, VSA functions cannot be cancelled by pressing the VSA OFF switch.

To determine the actual cause of the problem, question the client about the problem, taking these conditions To determine the actual cause of the problem, question the client about the problem, taking these conditions into consideration.

into consideration.



 When a problem is detected and the ABS indicator and VSA indicator come on, there are cases whenWhen a problem is detected and the ABS indicator and VSA indicator come on, there are cases when

the indicator stays on until the ignition switch is turned OFF, and cases when the indicator goes off the indicator stays on until the ignition switch is turned OFF, and cases when the indicator goes off automatically when the system returns to normal.

automatically when the system returns to normal.



 DTC 61 or 62:DTC 61 or 62:

The ABS and VSA indicators go off automatically when the system returns to normal. The ABS and VSA indicators go off automatically when the system returns to normal.

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2005-08 BRAKES VSA (Vehicle Stability Assist) System Components - RL 2005-08 BRAKES VSA (Vehicle Stability Assist) System Components - RL

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VSA indicator and VSA activation indicators turn on. VSA indicator and VSA activation indicators turn on.



 When all functions are lost:When all functions are lost:

All four indicators turn on. All four indicators turn on.



 When the gauge control module detects F-CAN circuit problem:When the gauge control module detects F-CAN circuit problem:

VSA indicator and brake system indicators turn on. VSA indicator and brake system indicators turn on.

Fig. 2: Identifying ABS Indicator, VSA Indicator And VSA Activation Indicator Fig. 2: Identifying ABS Indicator, VSA Indicator And VSA Activation Indicator Courtesy of AMERICAN HONDA MOTOR CO., INC.

Courtesy of AMERICAN HONDA MOTOR CO., INC. ABS/VSA INDICATOR

ABS/VSA INDICATOR

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 If the system is OK, the ABS and VSA indicators will go off 2 seconds after turning the ignitionIf the system is OK, the ABS and VSA indicators will go off 2 seconds after turning the ignition

switch ON (II). switch ON (II).



 The ABS and VSA indicators come on when the control unit detects a problem in the system.The ABS and VSA indicators come on when the control unit detects a problem in the system.

However, even though the system is operating properly, the activation indicator may come on under However, even though the system is operating properly, the activation indicator may come on under these conditions:

these conditions:



 One drive wheel is stuck.One drive wheel is stuck. 

 The vehicle goes into a spin.The vehicle goes into a spin. 

 The ABS or VSA continues to operate for a long time.The ABS or VSA continues to operate for a long time. 

 The vehicle is subjected to an electrical signal disturbance.The vehicle is subjected to an electrical signal disturbance. 

 The VSA switch has been manually turned off.The VSA switch has been manually turned off. 

 When an abnormality in the TPMS (Tire Pressure Monitoring System) or low tire pressure isWhen an abnormality in the TPMS (Tire Pressure Monitoring System) or low tire pressure is

detected, VSA functions cannot be cancelled by pressing the VSA OFF switch. detected, VSA functions cannot be cancelled by pressing the VSA OFF switch.

To determine the actual cause of the problem, question the client about the problem, taking these conditions To determine the actual cause of the problem, question the client about the problem, taking these conditions into consideration.

into consideration.



 When a problem is detected and the ABS indicator and VSA indicator come on, there are cases whenWhen a problem is detected and the ABS indicator and VSA indicator come on, there are cases when

the indicator stays on until the ignition switch is turned OFF, and cases when the indicator goes off the indicator stays on until the ignition switch is turned OFF, and cases when the indicator goes off automatically when the system returns to normal.

automatically when the system returns to normal.



 DTC 61 or 62:DTC 61 or 62:

The ABS and VSA indicators go off automatically when the system returns to normal. The ABS and VSA indicators go off automatically when the system returns to normal.

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 DTC 11, 13, 15, 17, 31, 32, 33, 34, 35, 36, 37, 38, DTC 11, 13, 15, 17, 31, 32, 33, 34, 35, 36, 37, 38, 53, 54, 71, 81, 112, 121, 122, 123 or 124:53, 54, 71, 81, 112, 121, 122, 123 or 124:

The ABS and VSA indicators stay on until the ignition switch is turned OFF whether or not the The ABS and VSA indicators stay on until the ignition switch is turned OFF whether or not the system returns to normal.

system returns to normal.

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 DTC 12,14,16,18, 21, 22, 23, 24, 41, 42, 43, 44, 51 or 52:DTC 12,14,16,18, 21, 22, 23, 24, 41, 42, 43, 44, 51 or 52:

The ABS and VSA indicators stay on until the system returns to normal after the vehicle is The ABS and VSA indicators stay on until the system returns to normal after the vehicle is driven.

driven.

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 DTC 25, 26, 27, 28, 64, 65, 66, 68,83, 84 or 86:DTC 25, 26, 27, 28, 64, 65, 66, 68,83, 84 or 86:

The VSA indicators stay on until the ignition switch is turned OFF whether or not the system The VSA indicators stay on until the ignition switch is turned OFF whether or not the system returns to normal.

returns to normal.

DIAGNOSTIC TROUBLE CODE (DTC) DIAGNOSTIC TROUBLE CODE (DTC)

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 The memory can hold any number of DTCs. However, when the same DTC is detected more thanThe memory can hold any number of DTCs. However, when the same DTC is detected more than

once, the more recent DTC is written over the earlier one. Therefore, when the same problem is once, the more recent DTC is written over the earlier one. Therefore, when the same problem is detected repeatedly, it is memorized as a single DTC.

detected repeatedly, it is memorized as a single DTC.

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 The DTCs are indicated in ascending number order, not in the order they occur.The DTCs are indicated in ascending number order, not in the order they occur. 

 The DTCs are memorized in the EEPROM (non-volatile memory). Therefore, the memorized DTCsThe DTCs are memorized in the EEPROM (non-volatile memory). Therefore, the memorized DTCs

cannot be canceled by disconnecting the battery. Do the specified procedures to clear the DTCs. cannot be canceled by disconnecting the battery. Do the specified procedures to clear the DTCs. SELF-DIAGNOSIS

SELF-DIAGNOSIS



 Self-diagnosis can be classified into two categories:Self-diagnosis can be classified into two categories: 

 Initial diagnosis: Done right after the ignition switch is turned ON (II) and until the ABS andInitial diagnosis: Done right after the ignition switch is turned ON (II) and until the ABS and

VSA indicators go off. VSA indicators go off.

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 Regular diagnosis: Done right after the initial diagnosis until the ignition switch is turned OFF.Regular diagnosis: Done right after the initial diagnosis until the ignition switch is turned OFF. 

 When the system detects a problem, the VSA modulator-control unit shifts to fail-safe mode.When the system detects a problem, the VSA modulator-control unit shifts to fail-safe mode.

KICKBACK KICKBACK

The pump motor operates when the ABS or VSA is functioning, and the fluid in the reservoir is forced out The pump motor operates when the ABS or VSA is functioning, and the fluid in the reservoir is forced out to the master cylinder, causing kickback at the brake pedal.

to the master cylinder, causing kickback at the brake pedal. PUMP MOTOR

PUMP MOTOR

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 The pump motor operates when the ABS or VSA is functioning.The pump motor operates when the ABS or VSA is functioning. 

 The VSA modulator-control unit checks the pump motor operation one time after completing initialThe VSA modulator-control unit checks the pump motor operation one time after completing initial

diagnosis during initial diagnosis when the vehicle is driven over 10 mph (15 km/h). You may hear diagnosis during initial diagnosis when the vehicle is driven over 10 mph (15 km/h). You may hear the motor operate at this time, but that is normal.

the motor operate at this time, but that is normal. BRAKE FLUID REPLACEMENT/AIR BLEEDING BRAKE FLUID REPLACEMENT/AIR BLEEDING

Brake fluid replacement and air bleeding procedures are identical to the procedures used on vehicles not Brake fluid replacement and air bleeding procedures are identical to the procedures used on vehicles not equipped with VSA (see

equipped with VSA (see BRAKE SYSTEM BLEEDINGBRAKE SYSTEM BLEEDING ).). 200

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2005-08 BRAKES VSA (Vehicle Stability Assist) System Components - RL 2005-08 BRAKES VSA (Vehicle Stability Assist) System Components - RL

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HOW TO TROUBLESHOOT DTCS

The troubleshooting flowchart procedures assume that the cause of the problem is still present and the ABS and/or VSA indicator are still on. Following the flowchart when the ABS and/or VSA indicators do not come on can result in incorrect diagnosis. The connector illustrations show the female terminal connectors with a single outline and the male terminal connectors with a double outline.

1. Question the client about the conditions when the problem occurred, and try to reproduce the same conditions for troubleshooting. Find out when the ABS and/or VSA indicators came on, such as during braking, accelerating, or turning, etc.

2. When the ABS and VSA indicators do not come on during the test-drive, but troubleshooting is done based on the DTC, check for loose connectors, poor contact of the terminals, etc. before you start

troubleshooting.

3. After troubleshooting or repairs are done, clear the DTCs, and test-drive the vehicle under the same conditions that originally set the DTCs. Make sure the ABS and VSA indicators do not come on. 4. Check for DTCs from other control units which are connected via F-CAN. If there are DTCs that are

related to F-CAN, the most likely cause was that the ignition switch was turned ON (II) with the VSA modulator-control unit connector disconnected. Clear the DTCs. Check for fuel and emissions, and VSA codes, first. Be sure to troubleshoot those first.

INTERMITTENT FAILURES

The team "intermittent failure" means a system may have had a failure, but it checks OK now. If the

indicator(s) of the system on the dash does not come on, check for poor connections or loose terminals at all connectors related to the circuit that you are troubleshooting. If the indicators were on but then went out, the original problem may have been intermittent.

HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM)

1. If the system indicators stay on, connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.

Fig. 3: Identifying Data Link Connector

Courtesy of AMERICAN HONDA MOTOR CO., INC. 2. Turn the ignition switch ON (II).

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troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).

4. Check the diagnostic trouble code (DTC) and note it. Also check the on-board snapshot data, and download any data found. Then refer to the indicated DTC's troubleshooting, and do the appropriate troubleshooting procedure.

HOW TO RETRIEVE DTCS

1. With the ignition switch OFF, connect the HDS to the data link connector (DLC) under the driver's side of the dashboard.

2. Turn the ignition switch ON (II).

3. Make sure the HDS communicates with the vehicle and the VSA modulator-control unit. If it doesn't, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).

4. Follow the prompts on the HDS to display the DTC(s) on the screen. After determining the DTC, refer to the DTC TROUBLESHOOTING.

5. Turn the ignition switch OFF. HOW TO CLEAR DTCS

1. With the ignition switch OFF, connect the HDS to the data link connector (DLC) under the driver's side of the dashboard.

3. Make sure the HDS communicates with the vehicle and the VSA modulator-control unit. If it doesn't, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).

4. Clear the DTC(s) by following the screen prompts on the HDS. 5. Turn the ignition switch OFF.

DTC TROUBLESHOOTING INDEX

DTC TROUBLESHOOTING CHART

NOTE: _ _{The HDS can r ead t he DTC, the curr ent data, and ot her sys tem} data.

 For specifi c operation s, refer to the Help menu that came wit h the HDS.

DTC DetectionItem

11 Right-front wheel sensor (short to power/short to body ground/open)

12 Right-front wheel sensor (electrical noise/intermittent interruption)

13 Left-front wheel sensor (short to power/short to body ground/open)

14 Left-front wheel sensor (electrical noise/intermittent interruption)

15 Right-rear wheel sensor (short to power/short to body ground/open)

16 Right-rear wheel sensor (electrical 2007 Acura RL

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SYMPTOM TROUBLESHOOTING INDEX

SYMPTOM TROUBLESHOOTING CHART

SYSTEM DESCRIPTION

VSA MODULATOR-CONTROL UNIT INPUTS AND OUTPUTS FOR 47P CONNECTOR

(CONNECTOR ATTACHED TO THE VSA MODULATOR-CONTROL UNIT. BACKPROBE THE TERMINALS WHEN TESTING.)

Fig. 4: Identifying VSA Modulator-Control Unit Inputs And Outputs For 47P Connector

121 VSA solenoid

122 VSA solenoid

123 VSA solenoid

124 VSA solenoid

Symptom Diagnostic procedure

ABS indicator does not come on Symptom Troubleshooting (see ABS INDICATOR DOES NOT COME ON )

ABS indicator does not go off, and no DTCs are stored

Symptom Troubleshooting (see ABS INDICATOR DOES NOT GO OFF, AND NO DTCS ARE STORED )

Brake system indicator does not come on (check bulb operation with parking brake)

Symptom Troubleshooting (see BRAKE SYSTEM INDICATOR DOES NOT COME ON (CHECK BULB OPERATION WITH PARKING BRAKE) )

Brake system indicator does not go off, and no DTCs are stored

Symptom Troubleshooting (see BRAKE SYSTEM INDICATOR DOES NOT GO OFF, AND NO DTCS ARE STORED )

VSA indicator does not come on Symptom Troubleshooting (see VSA INDICATOR DOES NOT COME ON )

VSA indicator does not go off, and no DTCs are stored

Symptom Troubleshooting (see VSA INDICATOR DOES NOT GO OFF, AND NO DTCS ARE STORED )

VSA activation indicator does not come on at start-up (bulb check)

Symptom Troubleshooting (see VSA ACTIVATION

INDICATOR DOES NOT COME ON AT START-UP (BULB CHECK) )

VSA activation indicator does not go off, and no DTCs are stored

Symptom Troubleshooting (see VSA ACTIVATION

INDICATOR DOES NOT GO OFF, AND NO DTCS ARE STORED )

HDS does not communicate with the VSA modulator-control unit or the vehicle

Troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).

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ABS Features

When the brake pedal is pressed while driving, the wheels can lock before the vehicle comes to a stop. In such an event, the maneuverability of the vehicle is reduced if the front wheels are locked, and the stability of the vehicle is reduced if the rear wheels are locked, creating an extremely unstable condition. The ABS precisely controls the slip rate of the wheels to ensure maximum grip force from the tires, and it thereby

ensures maneuverability and stability of the vehicle.

The ABS calculates the slip rate of the wheels based on the vehicle speed and the wheel speed, then it controls the brake fluid pressure to reach the target slip rate.

Grip Force of Tire and Road Surface

Fig. 6: Grip Force Of Tire And Road Surface Graph Courtesy of AMERICAN HONDA MOTOR CO., INC.

TCS Features

The TCS provides low-speed traction. When a drive wheel loses traction on a slippery road surface and starts to spin, the VSA modulator-control unit applies brake press ure to slow the spinning wheel. At that time, the VSA modulator-control unit sends a traction control signal to the PCM to reduce engine power.

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Fig. 7: Identifying TCS Traction Control Signal

Courtesy of AMERICAN HONDA MOTOR CO., INC. VSA SYSTEM FEATURES

Oversteer control

Applies the brakes to the front and rear outside wheels

Fig. 8: Applying Brakes To Front And Rear Outside Wheels - With VSA Courtesy of AMERICAN HONDA MOTOR CO., INC.

Understeer control (in acceleration)

 Applies the brakes to the front and rear inside wheels  Controls the engine torque

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Fig. 9: Applying Brakes To Front And Rear Inside Wheels - Without VSA Courtesy of AMERICAN HONDA MOTOR CO., INC.

ELECTRONIC BRAKE DISTRIBUTION (EBD)

Electronic Brake Distribution (EBD) has been added to the VSA system. EBD eliminates the need for an external, mechanical proportioning valve and improves overall braking performance.

When the vehicle is heavily loaded, most of the increase in weight is born by the rear wheels, increasing braking capability. Proportioning valves maintain a fixed distribution of brake pressure between the front

and the rear wheels, making it very difficult to fully utilize increased rear wheel braking capability. EBD varies brake pressure distribution according to load, using input from the wheel speed sensors, which improves overall braking performance.

Fig. 10: Electronic Brake Distribution Graph

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Normal Braking

Under normal braking conditions, brake pressure is evenly distributed between the front and rear brakes, and EBD is not used.

Firm Braking

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maximum amount of brake distribution individually to the rear wheels. Once the VSA modulator-control unit detects that one or both rear wheels are nearing their maximum braking potential, the inlet valve closes for one or both rear wheels, maintaining the current pressure. If the traction is improved, and the wheel(s) is no longer nearing its limits, the VSA modulator-control unit will open the inlet solenoid allowing additional pressure to be distributed to the rear wheel. The rear wheels are controlled independently of each other

during EBD function.

If during EBD function the VSA modulator-control unit determines that the wheels ar e beginning to slip more than a predetermined amount, the control unit abandons EBD control and shifts to select low 3-channel ABS control.

BRAKE ASSIST

Brake assist has been added to the VSA system. Brake assist helps ensure that any driver can achieve the full braking potential of the vehicle by increasing brake system pressure in a panic situation, bringing the vehicle into a full ABS stop.

Each time the ignition switch is turned ON (II), the VSA modulator-control unit learns the current driver's normal braking characteristics by monitoring the brake pressure sensor and the brake pedal position switch at each stop. Using these inputs and their values, the VSA modulator-control unit is able to learn the driver's normal braking habits, and then determine the difference between a normal stop and a panic stop for the individual driver of the vehicle. If during a panic stop the VSA modulator-control unit determines that the brake system pressure increases above a learned threshold in less than a learned amount of time, the VSA

modulator-control unit engages brake assist.

Because the brake system pressure crossed the threshold before the time threshold had expired, the VSA modulator-control unit goes into brake assist mode.

Fig. 11: Brake Assist Mode Graph

Normal Braking

During normal braking conditions, brake assist does not affect brake system pressure.

Panic Stop

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During a panic stop, the control unit turns the VSA pump ON, and opens the inlet valve. This brings the brake system pressure up high enough to cause a full ABS stop. As soon as the brake pedal is released, brake assist is stopped and the brake system returns to normal operation.

MODULATOR UNIT

The modulator unit consists of the inlet solenoid valve, outlet solenoid valve, VSA normally open (NO) solenoid valve, VSA normally closed (NC) solenoid valve, reservoir, pump, pump motor, and the damping chamber.

The modulator controls the caliper fluid pressure directly. It is a circulating-type modulator because the brake fluid circulates through the caliper, the reservoir, and the master cylinder.

The hydraulic control has three modes: Pressure intensifying, pressure retaining, and pressure reducing. The hydraulic circuit is an independent four channel type, one channel for each wheel.

ABS CONTROL

Pressure intensifying mode

VSA NO valve open, VSA NC valve closed, inlet valve open, outlet valve closed. Master cylinder fluid is pumped out to the caliper.

Pump motor

When starting the pressure reducing mode, the pump motor is ON. When stopping ABS operation, the pump motor is OFF.

The reservoir fluid is pumped out by the pump, through the damping chamber, to the master cylinder.

Fig. 12: VSA System Diagram (Pump Motor)

Pressure retaining mode

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Caliper fluid is retained by the inlet valve and outlet valve.

Fig. 13: VSA System Diagram (Pressure Retaining Mode) Courtesy of AMERICAN HONDA MOTOR CO., INC.

Pressure reducing mode

VSA NO valve open, VSA NC valve closed, inlet valve closed, outlet valve open. Caliper fluid flows through the outlet valve to the reservoir.

Fig. 14: VSA System Diagram (Pressure Reducing Mode) Courtesy of AMERICAN HONDA MOTOR CO., INC. TCS CONTROL

VSA NO valve closed, VSA NC valve open, inlet valve open, outlet valve closed, pump motor ON. The reservoir and master cylinder fluid is pumped out by the pump, through the damping chamber, to the front caliper.

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Fig. 15: VSA System Diagram (Pressure Intensifying Mode) Courtesy of AMERICAN HONDA MOTOR CO., INC.

VSA NO valve closed, VSA NC valve open, inlet valve closed, outlet valve closed, pump motor ON. Front caliper fluid is retained by the inlet valve and outlet valve.

VSA NO valve open, VSA NC valve closed, inlet valve closed, front outlet valve open, pump motor ON. Caliper fluid flows through the outlet valve to the reservoir.

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Fig. 17: VSA System Diagram (Pressure Reducing Mode) Courtesy of AMERICAN HONDA MOTOR CO., INC. VSA CONTROL

VSA NO valve closed, VSA NC valve open, inlet valve open, outlet valve closed, pump motor ON. The reservoir and master cylinder fluid is pumped out by the pump, through the damping chamber, to the front and rear calipers.

Fig. 18: VSA System Diagram (Pressure Intensifying Mode) Courtesy of AMERICAN HONDA MOTOR CO., INC.

VSA NO valve closed, VSA NC valve open, inlet valve closed, outlet valve closed, pump motor ON. Front and rear caliper fluid is retained by the inlet valve and outlet valve.

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VSA NO valve open, VSA NC valve closed, inlet valve closed, outlet valve open, pump motor ON. Caliper fluid flows through the outlet valve to the reservoir.

Fig. 20: VSA System Diagram (Pressure Reducing Mode) Courtesy of AMERICAN HONDA MOTOR CO., INC.

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Fig. 21: VSA System - Circuit Diagram (1 Of 3)

Courtesy of AMERICAN HONDA MOTOR CO., INC. 2007 Acura RL

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DTC TROUBLESHOOTING

DTC 11, 13, 15, 17: WHEEL SENSOR (SHORT TO POWER/SHORT TO BODY GROUND/OPEN) 1. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ).

2. Disconnect the HDS.

3. Turn the ignition switch OFF, then ON (II) again. 4. Test-drive the vehicle.

Do the VSA and ABS indicators come on? YES - Go to step 5.

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NO - Intermittent failure; system is OK at this time (see INTERMITTENT FAILURES ). Check for loose or poor connections.

5. Disconnect the VSA modulator-control unit 47P connector. 6. Start the engine.

7. Measure the voltage between body ground and the appropriate wheel sensor +B and GND terminals of the VSA modulator-control unit 47P connector individually (see DTC TERMINAL CHART). DTC TERMINAL CHART

Fig. 24: Measuring Voltage Between Body Ground And Appropriate Wheel Sensor +B Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there 0.1 V or more?

YES - Repair short to power in the wire between the VSA modulator-control unit and the appropriate wheel sensor.

NO - Go to step 8.

8. Turn the ignition switch OFF.

9. Check for continuity between body ground and the appropriate wheel sensor +B and GND terminals of the VSA modulator-control unit 47P connector individually (see DTC TERMINAL CHART). DTC TERMINAL CHART

DTC Appropriate Terminal

+B GND

11 (Right-front) FR+B: No. 18 FR-GND: No. 17 13 (Left-front) FL+B: No. 4 FL-GND: No. 20 15 (Right-rear) RR+B: No. 5 RR-GND: No. 6 17 (Left-rear) RL +B: No. 2 RL-GND: No. 3

+B GND

11 (Right-front) FR+B: No. 18 FR-GND: No. 17 13 (Left-fr t) FL+B: N 4 FL-GND: N 20

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Fig. 25: Checking Continuity Between Body Ground And Appropriate Wheel Sensor +B And GND Terminals Of VSA Modulator-Control Unit

Courtesy of AMERICAN HONDA MOTOR CO., INC. Is there continuity?

YES - Go to step 10. NO - Go to step 12.

10. Disconnect the appropriate wheel sensor 2P connector.

11. Check for continuity between body ground and the appropriate wheel sensor +B and GND terminals of the VSA modulator-control unit 47P connector individually (see DTC TERMINAL CHART). DTC TERMINAL CHART

15 (Right-rear) RR+B: No. 5 RR-GND: No. 6 17 (Left-rear) RL+B: No. 2 RL-GND: No. 3

+B GND

11 (Right-front) FR+B: No. 18 FR-GND: No. 17 13 (Left-front) FL+B: No. 4 FL-GND: No. 20 15 (Right-rear) RR+B: No. 5 RR-GND: No. 6 17 (Left-rear) RL+B: No. 2 RL-GND: No. 3

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Fig. 26: Checking Continuity Between Body Ground And Appropriate Wheel Sensor +B And GND Terminals Of VSA Modulator-Control Unit 47P Connector

YES - Repair short to body ground in the wire between the VSA modulator-control unit and the wheel sensor.

NO - Replace the appropriate wheel sensor (see WHEEL SENSOR REPLACEMENT ). 12. Disconnect the appropriate wheel sensor 2P connector.

13. Check for continuity between the appropriate wheel sensor +B and GND terminals of the VSA modulator-control unit 47P connector (see DTC TERMINAL CHART).

DTC TERMINAL CHART

+B GND

11 (Right-front) FR +B: No, 18 FR-GND: No. 17 13 (Left-front) FL+B: No. 4 FL-GND: No. 20 15 (Right-rear) RR+B: No. 5 RR-GND: No. 6 17 (Left-rear) RL+B: No. 2 RL-GND: No. 3

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Fig. 27: Checking Continuity Between Appropriate Wheel Sensor +B And Gnd Terminals Of VSA Modulator-Control Unit 47P Connector

YES - Repair short in the wires between the VSA modulator-control unit and the wheel sensor. NO - Go to step 14.

14. Check for continuity between the appropriate +B and GND terminals of the VSA modulator-control unit 47P connector and the relative wheel sensor 2P connector.

Is there continuity? YES - Go to step 15.

NO - Repair open in the wire(s) between the VSA modulator-control unit 47P connector and the wheel sensor 2P connector.

15. Substitute a known-good wheel sensor for the appropriate wheel sensor (see DTC TERMINAL CHART).

DTC TERMINAL CHART

16. Clear the DTCs using the HDS (see HOW TO CLEAR DTCS ). 17. Disconnect the HDS from the 16P DLC.

18. Turn the ignition switch ON (II) and then OFF.

19. Turn the ignition switch ON (II), then test-drive the vehicle at speeds above 19 mph (30 km/h). DTC Appropriate Wheel Sensor

11 Right-front 13 Left-front 15 Right-rear 17 Left-rear

2007 Acura RL

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Does the ABS indicator come on?

YES - Check for loose terminals or poor connections at the VSA modulator-control unit 47P connector. If connections are good, replace the VSA modulator-control unit (see VSA

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. NO - Replace the original wheel sensor (see WHEEL SENSOR REPLACEMENT ). DTC 12, 14, 16, 18: WHEEL SENSOR (ELECTRICAL NOISE/INTERMITTENT INTERRUPTION)

1. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 2. Disconnect the HDS from the 16P DLC.

3. Turn the ignition switch OFF, then turn it ON (II) again. 4. Test-drive the vehicle around a number of corners.

Does the ABS indicator come on and is DTC 12, 14, 16 or 18 indicated? YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time.

5. Check the appropriate wheel sensor and magnetic encoder for debris or damage (see WHEEL SENSOR INSPECTION ).

DTC TERMINAL CHART

Is there debris or damage? YES - Go to step 6.

NO - Clean or replace wheel sensor or magnetic encoder. 6. Disconnect the VSA modulator-control unit 47P connector.

7. Check for continuity between the appropriate wheel sensor +B terminal and other wheel sensor +B terminals of the VSA modulator-control unit 47P connector (see DTC TERMINAL CHART). DTC TERMINAL CHART

NOTE: If the ABS indicator comes on because of electrical noise, the indicator goes off when you test-dri ve the vehicle at 19 mph (30 km/h).

DTC Appropriate Wheel Sensor 12 Right-front

14 Left-front 16 Right-rear 18 Left-rear

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Fig. 28: Identifying VSA Modulator-Control Unit 47P Connector Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair short in the wire between the appropriate wheel sensor and the other wheel sensor. NO - Go to step 8.

8. Substitute a known-good wheel sensor for the appropriate wheel sensor (see DTC TERMINAL CHART).

DTC TERMINAL CHART

11. Turn the ignition switch ON (II), then turn it OFF.

12. Turn the ignition switch ON (II), then test-drive the vehicle around a number of corners. Does the ABS indicator come on?

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck.

NO - Replace the original wheel sensor or encoder (see WHEEL SENSOR REPLACEMENT ). 12 FR +B: No. 18 No. 4 No. 5 No. 2

14 FL +B: No. 4 No. 18 No. 5 No. 2 16 RR+B: No. 5 No. 18 No. 4 No. 2 18 RL+B: No. 2 No. 18 No. 4 No. 5

DTC Appropriate Wheel Sensor 12 Right-front

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DTC 21, 22, 23, 24: MAGNETIC ENCODER (WHEEL BEARING) 1. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 2. Disconnect the HDS from the 16P DLC.

3. Turn the ignition switch OFF, then turn it ON (II) again. 4. Test-drive the vehicle at 19 mph (30 km/h) or more.

Does the ABS indicator come on? YES - Go to step 5.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES .

5. Check the appropriate magnetic encoder for debris or damage (see DTC TERMINAL CHART) (see WHEEL SENSOR INSPECTION ).

DTC TERMINAL CHART

Is the encoder OK? YES - Go to step 6.

NO - Clean and reinstall or replace the magnetic encoder.

6. Clear the DTCs using the HDS (see HOW TO CLEAR DTCS ). 7. Disconnect the HDS from the 16P DLC.

8. Turn the ignition switch OFF, then turn it ON (II) again. 9. Test-drive the vehicle at speeds above 19 mph (30 km/h).

Does the ABS indicator come on, and are DTCs 21, 22,23, and/or 24 indicated?

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. NO - Replace the original magnetic encoder (see WHEEL SENSOR REPLACEMENT ), or encoder/wheel bearing:

 Front hub/bearing unit (see KNUCKLE/HUB BEARING UNIT REPLACEMENT )  Rear hub/bearing unit (see KNUCKLE/HUB BEARING UNIT REPLACEMENT )

DTC 25: YAW RATE SENSOR DTC Appropriate Encoder

21 Right-front 22 Left-front 23 Right-rear 24 Left-rear

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3. Turn the ignition switch OFF, then turn it ON (II) again. 4. Test-drive the vehicle around a number of corners. 5. Verify the DTC.

Is DTC 25 indicated? YES - Go to step 6.

NO - The system is OK at this time. Check for loose terminals or poor connections. 6. Turn the ignition switch OFF.

7. Disconnect the VSA modulator-control unit 47P connector, steering angle sensor 5P connector and yaw rate-lateral/longitudinal acceleration sensor 5P connector.

9. Measure the voltage between body ground and the VSA modulator-control unit 47P connector terminals No. 33, No. 34, and No. 35 individually.

Fig. 29: Measuring Voltage Between Body Ground And VSA Modulator-Control Unit 47P Connector Terminals No. 33, No. 34, And No. 35

Courtesy of AMERICAN HONDA MOTOR CO., INC. Is there 0.1 V or more?

YES - Repair short to power in the wire between the VSA modulator-control unit, the yaw rate-lateral/longitudinal acceleration sensor and the steering angle sensor.

NO - Go to step 10.

11. Check for continuity between body ground and the VSA modulator-control unit 47P connector terminals No. 33, No. 34, and No. 35 individually.

NOTE: If DTC 27 or 64 is stored at the same time as DTC 25, troubleshoot those DTCs fir st, t hen recheck f or DTC 25.

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Fig. 30: Checking Continuity Between Body Ground And VSA Modulator-Control Unit 47P Connector Terminals No. 33, No. 34, And No. 35

YES - Repair short to body ground in the wire between the VSA modulator-control unit, the yaw rate-lateral/longitudinal acceleration sensor, and the steering angle sensor.

NO - Go to step 12.

12. Check for continuity between the VSA modulator-control unit 47P connector terminal No. 35 and yaw rate-lateral/longitudinal acceleration sensor 5P connector terminal No. 2.

Fig. 31: Checking Continuity Between VSA Modulator-Control Unit Terminal No. 35 And Yaw Rate-Lateral/Longitudinal Sensor 5P Connector Terminal No. 2

YES - Go to step 13.

NO - Repair open in the wire between the VSA modulator-control unit and the yaw rate-lateral/longitudinal acceleration sensor.

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Fig. 32: Checking Continuity Between VSA Modulator-Control Unit Connector Terminal No. 33 And Yaw Rate-Lateral/Longitudinal Sensor Connector Terminal No. 4

Fig. 33: Checking Continuity Between VSA Modulator-Control Unit 47P Connector Terminal No. 34 And Yaw Rate-Lateral/Longitudinal 5P Connector Terminal No. 3

15. Substitute a known-good yaw rate-lateral/longitudinal acceleration sensor. 16. Reconnect all of the disconnected connectors.

17. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 2007 Acura RL

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21. Verify the DTC. Is DTC 25 indicated?

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. NO - Replace the original yaw rate-lateral/longitudinal acceleration sensor (see YAW RATE-LATERAL/LONGITUDINAL ACCELERATION SENSOR REPLACEMENT ).

DTC 26: LATERAL ACCELERATION SENSOR

YES - Go to step 6.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES . 6. Turn the ignition switch OFF.

7. Disconnect the VSA modulator-control unit 47P connector, steering angle sensor 5P connector, and yaw rate-lateral/longitudinal acceleration sensor 5P connector.

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YES - Repair short to power in the wire between the VSA modulator-control unit, the yaw rate-lateral/longitudinal acceleration sensor, and the steering angle sensor.

NO - Go to step 10.

NO - Go to step 12.

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Fig. 36: Checking Continuity Between VSA Modulator-Control Unit Terminal No. 35 And Yaw Rate-Lateral/Longitudinal Connector Terminal No. 2

Fig. 37: Checking Continuity Between VSA Modulator-Control Unit Terminal No. 33 And Yaw Rate-Lateral/Longitudinal Connector Terminal No. 4

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Rate-Lateral/Longitudinal Connector Terminal No. 1 Courtesy of AMERICAN HONDA MOTOR CO., INC. Is there continuity?

15. Substitute a known-good yaw rate-lateral/longitudinal acceleration sensor. 16. Reconnect all of the disconnected connectors.

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. NO - Replace the original yaw rate-lateral/longitudinal acceleration sensor (see YAW RATE-LATERAL/LONGITUDINAL ACCELERATION SENSOR REPLACEMENT ).

DTC 27: STEERING ANGLE SENSOR

YES - Go to step 6.

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8. Disconnect the SH-AWD control unit 26P connector and the adaptive front lighting control unit 40P connector.

10. Measure the voltage between body ground and the VSA modulator-control unit 47P connector terminals No. 33 and No. 35 individually.

Fig. 39: Measuring Voltage Between Body Ground And VSA Modulator-Control Unit 47P Connector Terminals No. 33 And No. 35

YES - Repair short to power in the wire between the VSA modulator-control unit, the steering angle sensor, and the yaw rate-lateral/longitudinal acceleration sensor.

NO - Go to step 11.

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NO - Go to step 12.

13. Check for continuity between body ground and the VSA modulator-control unit 47P connector terminals No. 33 and No. 35 individually.

Fig. 41: Checking Continuity Between Body Ground And VSA Modulator-Control Unit 47P Connector Terminals No. 33 And No. 35

YES - Repair short to body ground in the wire between the VSA modulator-control unit, the steering angle sensor, and the yaw rate-lateral/ longitudinal acceleration sensor.

NO - Go to step 14.

YES - Repair short to body ground in the wire between the VSA modulator-control unit, the steering angle sensor, and the yaw rate-lateral/longitudinal acceleration sensor.

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NO - Go to step 15.

15. Check for continuity between the VSA modulator-control unit 47P connector terminals No. 33, No. 35 and steering angle sensor 5P connector terminals No. 1, No. 5 respectively.

Fig. 43: Checking Continuity Between VSA Modulator-Control Unit Terminals No. 33, No. 35 And Steering Angle Terminals No. 1, No. 5

NO - Repair open in the wire between the VSA modulator-control unit and the steering angle sensor. 16. Check for continuity between the VSA modulator-control unit 47P connector terminals No. 28, No.

29, No. 43 and steering angle sensor 5P connector terminals No. 2, No. 3, No. 4 respectively.

Fig. 44: Checking Continuity Between VSA Modulator-Control Unit Terminals No. 28, No. 29, No. 43 And Steering Angle Sensor Terminals No. 2, No. 3, No. 4

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17. Substitute a known-good steering angle sensor. 18. Reconnect all of the disconnected connectors.

YES - Check for loose terminals or poor connections at the VSA modulator-control unit 47P

connector and the steering angle sensor 5P connector, and repair if necessary. If no poor connections are found, replace the VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).

NO - Replace the original steering angle sensor (see STEERING ANGLE SENSOR REPLACEMENT ).

DTC 28: LONGITUDINAL ACCELERATION SENSOR

1. Clear the DTC, and disconnect the HDS (see HOW TO CLEAR DTCS ). 2. Turn the ignition switch OFF, then turn it ON (II) again.

3. Test-drive the vehicle around a number of corners. 4. Verify the DTC.

Is DTC 28 indicated? YES - Go to step 5.

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Fig. 45: Measuring Voltage Between Body Ground And VSA Modulator-Control Unit Terminals No. 33, No. 35, And No. 39

YES - Repair short to power in the wire between the VSA modulator-control unit and the yaw rate-lateral/longitudinal acceleration sensor.

NO - Go to step 9.

Fig. 46: Checking Continuity Between Body Ground And VSA Modulator-Control Unit 47P Connector Terminals No. 33, No. 35 And No. 39

YES - Repair short to body ground in the wire between the VSA modulator-control unit and the yaw rate-lateral/longitudinal acceleration sensor.

NO - Go to step 11.

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Fig. 47: Checking Continuity Between VSA Modulator-Control Unit Terminal No. 35 And Yaw Rate-Lateral/Longitudinal Acceleration Sensor Terminal No. 2

Fig. 48: Checking Continuity Between VSA Modulator-Control Unit Terminal No. 33 And Yaw Rate-Lateral/Longitudinal Sensor Terminal No. 4

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Fig. 49: Checking Continuity Between VSA Modulator-Control Terminal No. 39 And Yaw Rate-Lateral/Longitudinal Terminal No. 5

14. Reconnect all of the disconnected connectors. 15. Turn the ignition switch ON (II).

16. Measure the voltage between body ground and the VSA modulator-control unit 47P connector terminals No. 32 and No. 47 individually.

Fig. 50: Measuring Voltage Between Body Ground And VSA Modulator-Control Unit 47P Connector Terminals No. 32 And No. 47

Courtesy of AMERICAN HONDA MOTOR CO., INC. Is there 0.1 V or less?

NO - Repair open in the wire between the VSA modulator-control unit and body ground (G202). If the wire is OK, check for a poor connection at body ground (G202).

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19. Disconnect the HDS from the 16P DLC.

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. NO - Replace the yaw rate-lateral/longitudinal acceleration sensor (see YAW

RATE-LATERAL/LONGITUDINAL ACCELERATION SENSOR REPLACEMENT ). DTC 31, 32, 33, 34, 35, 36, 37, 38: ABS SOLENOID

1. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 2. Turn the ignition switch ON (II).

3. Verify the DTC.

Does the ABS indicator come on, and are DTCs 31, 32, 33, 34, 35, 36, 37, and/or 38 indicated? YES - Check for loose terminals or poor connections at the VSA modulator-control unit 47P connector. If connections are good, replace the VSA modulator-control unit (see VSA

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. NO - The system is OK at this time. Refer to INTERMITTENT FAILURES .

DTC 41, 42, 43, 44: WHEEL LOCK

4. Check for brake drag; test-drive the vehicle using the brake often, lift the vehicle on the hoist, rotate each tire by hand.

Do the brakes drag?

YES - Repair the brake drag. NO - Go to step 5.

5. Check the installation of the appropriate wheel sensor and magnetic encoder for damage, debris, or excessive air gap (see WHEEL SENSOR INSPECTION ).

DTC TERMINAL CHART

DTC Appropriate Wheel Sensor

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Is it correct?

YES - If the DTC does not reappear, the most probable cause for the DTC is that the vehicle might have lost traction in poor weather and spun around.

NO - Reinstall or replace the wheel sensor (see WHEEL SENSOR REPLACEMENT ) or magnetic encoder: Front (see KNUCKLE/HUB BEARING UNIT REPLACEMENT ), rear (see

KNUCKLE/HUB BEARING UNIT REPLACEMENT ). DTC 51: MOTOR LOCK; DTC 52: MOTOR STUCK OFF

Does the VSA indicator come on and is DTC 51 or 52 stored? YES - Go to step 5.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES . 5. Check the No. 17 (30 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES - Reinstall the fuse, and go to step 6. NO - Replace the fuse, and recheck.

6. Disconnect the VSA modulator-control unit 47P connector.

7. Measure the voltage between the VSA modulator-control unit 47P connector terminal No. 16 and body ground.

Fig. 51: Measuring Voltage Between VSA Modulator-Control Unit Terminal No. 16 And Body 41 Right-front

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Ground

Courtesy of AMERICAN HONDA MOTOR CO., INC. Is there battery voltage?

YES - Go to step 8.

NO - Repair open in the wire between the No. 17 (30 A) fuse and the VSA modulator-control unit. 8. Turn the ignition switch ON (II).

9. Check for continuity between the VSA modulator-control unit 47P connector terminal No. 47 and body ground.

Fig. 52: Checking Continuity Between VSA Modulator-Control Unit 47P Connector Terminal No. 47 And Body Ground

NO - Repair open in the wire between the VSA modulator-control unit and body ground (G202). 10. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ).

11. Turn the ignition switch OFF, then turn it ON (II) again. 12. Test-drive the vehicle at 10 mph (15 km/h) or more.

Does the ABS indicator come on, and is DTC 51 or 52 indicated?

DTC 53: MOTOR STUCK ON

1. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 2007 Acura RL

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3. Turn the ignition switch OFF, then turn it ON (II) again.

4. Test-drive the vehicle around a number of corners, and leave the ignition switch ON (II). Does the VSA indicator come on and is DTC 53 stored?

YES - Go to step 5.

YES - Go to step 8.

NO - Repair open or high resistance in the wire between the VSA modulator-control unit and body ground (G202).

8. Reconnect the VSA modulator-control unit 47P connector.

9. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 10. Turn the ignition switch OFF, then turn it ON (II) again.

11. Test-drive the vehicle.

Does the ABS indicator come on, and is DTC 53 indicated?

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DTC 54: FAIL-SAFE RELAY

3. Turn the ignition switch OFF, then turn it ON (II) again.

4. Test-drive the vehicle around a number of corners, and leave the ignition switch ON (II). Does the VSA indicator come on and is DTC 54 stored?

YES - Go to step 5.

YES - Go to step 8.

NO - Repair open or high resistance in the wire between the VSA modulator-control unit and body ground (G202).

8. Reconnect the VSA modulator-control unit 47P connector.

9. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 10. Turn the ignition switch OFF, then turn it ON (II) again.

11. Test-drive the vehicle.

YES - Check for loose terminals or poor connections at the VSA modulator-control unit 47P 2007 Acura RL

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DTC 61,62: LOW/HIGH VOLTAGE

Does the ABS indicator come on? YES - Go to step 5.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES . 5. Verify the DTC.

Is DTC 61 or 62 indicated?

YES - Check the battery (see BATTERY TEST ) and the charging system (see ALTERNATOR CONTROL CIRCUIT TROUBLESHOOTING ).

NO - Do the appropriate troubleshooting for the DTC indicated. DTC 64: SENSOR POWER VOLTAGE

Does the VSA indicator come on and is DTC 64 stored? YES - Go to step 5.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES .

5. Disconnect the VSA modulator-control unit 47P connector, the steering angle sensor 5P connector, and the yaw rate-lateral/longitudinal acceleration sensor 5P connector.

6. Start the engine.

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Fig. 55: Measuring Voltage Between VSA Modulator-Control Unit 47P Connector Terminal No. 35 And Body Ground

YES - Repair short to power in the wire between the VSA modulator-control unit and yaw rate-lateral/longitudinal acceleration sensor and steering angle sensor.

NO - Go to step 8.

YES - Repair short to body ground in the wire between the VSA modulator-control unit and yaw rate-lateral/longitudinal acceleration sensor and steering angle sensor.

NO - Go to step 10.

10. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ). 11. Test-drive the vehicle.

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MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES and check connections at the VSA modulator-control unit 47P connector and body ground (G202).

DTC 65: BRAKE FLUID LEVEL 1. Check the brake fluid level.

Is the level correct? YES - Go to step 2.

NO - Inspect the brake system for fluid leaks. If no leaks are found, check for all worn brake pads. 2. Disconnect gauge control module connector B (28P) and brake fluid level switch 2P connector. 3. Check for continuity between terminal No. 13 of gauge control module connector B (28P) and body

ground.

Fig. 57: Checking Continuity Between Terminal No. 13 Of Gauge Control Module Connector B (28P) And Body Ground

YES - Repair short to body ground in the wire between gauge control module connector B and the brake fluid level switch.

NO - Go to step 4.

4. Check the brake fluid level switch (see PARKING BRAKE SWITCH TEST ). Is the switch OK?

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FUNCTION ).

NO - Replace the brake fluid level switch.

DTC 66: VSA PRESSURE SENSOR (INSIDE OF VSA MODULATOR-CONTROL UNIT) 1. Clear the DTC using the HDS (see HOW TO CLEAR DTCS ).

2. Remove the HDS from the 16P DLC.

3. Turn the ignition switch OFF, then turn it ON (II). 4. Test-drive the vehicle.

Does the ABS indicator come on, and is DTC 25, 26,27, or 64 indicated? YES - Do the appropriate troubleshooting for the DTC.

NO - Go to step 5.

5. Do the VSA sensor neutral position memorization (see VSA SENSOR NEUTRAL POSITION MEMORIZATION ).

DTC 68: BRAKE PEDAL POSITION SWITCH 1. Check for other DTCs in the PGM-FI system.

Are other DTCs indicated?

YES - Do the appropriate troubleshooting for the DTCs. NO - Go to step 2.

2. Check the brake pedal position switch (see BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT ).

Is the switch OK? YES - Go to step 3.

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NO - Adjust the brake pedal position switch (see BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT ).

Does the ABS indicator come on, and is DTC 68 indicated? YES - Go to step 7.

NO - The system is OK at this time. Refer to INTERMITTENT FAILURES . 7. Troubleshoot the brake pedal position switch circuit (see CIRCUIT DIAGRAM ).

Is the brake pedal position switch circuit OK? YES - Substitute a known-good PCM and recheck:

 If the problem is gone, replace the original PCM.

 If the problem continues, replace the VSA modulator-control unit (see VSA

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ). NO - Repair the brake pedal position switch circuit.

DTC 71: DIFFERENT DIAMETER TIRE

3. Turn the ignition switch OFF, then turn it ON (II) again. 4. Test-drive the vehicle.

NO - Confirm that tire inflation is set to spec. The vehicle is OK at this time. Refer to INTERMITTENT FAILURES .

5. Check that all four tires are the specified size and are inflated to the proper specification. Are all four tires the correct size and properly inflated?

YES - Go to step 6.

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6. With the vehicle on level ground, mark each tire with a small spot of grease. Roll the vehicle until each of the tires makes two grease spots on the floor.

7. Measure and record the distance between the two grease spots.

Is the difference between the shortest and the longest measurement more than 10%? YES - Replace the tire/tires that is smaller or larger than the others.

NO - Replace the VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).

DTC 81: CENTRAL PROCESSING UNIT (CPU) 1. Check for other DTCs.

Is another DTC indicated?

YES - Do the appropriate troubleshooting for the DTC. NO - Go to step 2.

4. Turn the ignition switch OFF, then turn it ON (II) again. 5. Test-drive the vehicle.

NO - The vehicle is OK at this time. Refer to INTERMITTENT FAILURES .

6. Disconnect the VSA modulator-control unit 47P connector, the steering angle sensor 5P connector, and the yaw rate-lateral/longitudinal acceleration sensor 5P connector.

7. Start the engine.

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35 And Body Ground

YES - Repair short to power in the wire between the VSA modulator-control unit, the yaw rate-lateral/longitudinal acceleration sensor, and the steering angle sensor.

NO - Go to step 9.

NO - Check for loose terminals or poor connections at the VSA modulator-control unit 47P connector. If connections are good, replace the VSA modulator-control unit (see VSA

MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), and recheck. DTC 83: PCM

1. Check the DTC. Is DTC 86 indicated?

YES - Do the troubleshooting for DTC 86 (see DTC 86: F-CAN COMMUNICATION ). NO - Go to step 2.