On-board diagnostics are functioning properly
Tech 2 values from a properly running engine may be used for comparison with the engine you are
diagnosing. The Tech 2 Data List represents values that would be seen on a normal running engine.
Tech 2 Parameter
Units Displayed
At Engine Idle
At Engine 2000RPM
Definitions
Operating Conditions: Engine Idling or 2000RPM / Engine Coolant Temperature is between 75-85°C (167-185°F) / Accelerator Pedal is Constant / Park or Neutral / Accessories OFF / Vehicle Located at Sea Level
Ignition Switch On / Off On On This parameter displays the input status of the ignition switch to the ECM J2-72 terminal. The Tech 2 will display On or Off. On indicates the ignition switch is turned ON position.
Ignition Voltage Volts 12.0-15.0 12.0-15.0 This parameter displays the ignition voltage measured by the ECM at the ignition feed circuit J2-72 terminal. Voltage is applied to the ECM when the ignition switch is ON position.
Battery Voltage Volts 12.0-15.0 12.0-15.0 This parameter displays the system voltage measured by the ECM at the ECM main relay voltage feed circuit J2-73 terminal.
Starter Switch On / Off Off Off This parameter displays the input status of the starter switch to the ECM J2-44 terminal. The Tech 2 will display On or Off. On indicates the ignition switch is turned at START position.
Park/ Neutral Switch
On / Off On On This parameter displays the input status of the P, N position switch (A/T) or neutral switch (M/T) to the ECM J2-3. The Tech 2 will display On or Off. On indicates the P, N position switch (A/T) or neutral switch (M/T) is ON position (actual position).
Intank Pump Relay Control
On / Off On On This parameter displays the commanded state of the fuel pump relay control circuit. The Tech 2 will display On or Off. On indicates the fuel pump control circuit is being grounded by the ECM J1-66 terminal, allowing voltage to the intank fuel pump. Off indicates the fuel pump relay is not being commanded ON by the ECM.
Notice: The fuel pump relay is commanded ON for 12 seconds at ignition switch is ON with the engine OFF.
Glow Relay Control
On / Off Off Off This parameter displays the commanded state of the glow relay control circuit.
The Tech 2 will display On or Off. On indicates the glow relay control circuit is being grounded by the ECM J2-37 terminal, allowing voltage to the glow plugs.
Off indicates the glow relay is not being commanded ON by the ECM.
A/C Clutch Switch
On / Off Off Off This parameter displays the state of the air conditioning (A/C) compressor relay control from the ECM J2-55 terminal. The Tech 2 will display On or Off. On indicates the ECM is receiving a request from the HVAC system and enables to ground the A/C compressor relay control circuit, engaging the A/C compressor clutch. Off indicates the ECM is not receiving a request from the HVAC system or system is disabled to ground the A/C compressor clutch relay control circuit.
Tech 2
On / Off On On This parameter displays the commanded state of the swirl control solenoid circuit. The Tech 2 will display On or Off. On indicates the swirl control solenoid circuit is being grounded by the ECM J1-67 terminal, allowing voltage to the solenoid valve. Off indicates the swirl control solenoid is not being commanded ON by the ECM.
Desired Idle Speed
RPM 700 700 The idle speed that is requested by the ECM. The ECM will change desired idle speed based on engine coolant temperature (ECT), battery voltage and A/C system status as follows.
When the ECT is lower than -10°C (14°F), the ECM set the desired idle speed to 800RPM. When the ECT is more than 30°C (86°F), the ECM set the desired idle speed to 700RPM.
If the battery voltage is less than 11 volts during the engine running with A/C system OFF, the ECM set the desired idle speed to 750RPM. And battery voltage is returned more than 12 volts with the A/C system OFF, the ECM set the desired idle speed to 700RPM.
If the A/C system is activated, the ECM sets 50RPM higher than normal idle speed.
Engine Speed RPM Nearly 700
RPM
Nearly 2000 RPM
This parameter displays the speed of the crankshaft signal input to the ECM J1-58 terminal from the crankshaft position (CKP) sensor. The Tech 2 will display the engine speed in revolution per minute (RPM).
Vehicle Speed km/h / MPH 0 0 This parameter indicates the vehicle speed calculated by the ECM based on input from the vehicle speed sensor (VSS) to the ECM J2-62 terminal. The Tech 2 will display a high value at higher vehicle speeds, and a low value at lower vehicle speeds.
Intake Air
This parameter displays the temperature of the intake air as calculated by the ECM using the signal input from the intake air temperature (IAT) sensor. The Tech 2 will display a low temperature when signal voltage is high and a high temperature when the signal voltage is low.
Notice: The intake air temperature sensor is internal to the MAF sensor and the MAF sensor is heated. If the ignition switch is being ON, it may indicate higher than normal intake temperature.
Intake Air Temperature
Sensor
Volts 1.4 - 2.6 1.4 - 2.6 This parameter displays the temperature of the intake air based on signal input from the intake air temperature (IAT) sensor to the ECM J1-41 terminal. The Tech 2 will display a low signal voltage when the temperature is high and a high signal voltage when the temperature is low.
Notice: the intake air temperature sensor is internal to the MAF sensor and the MAF sensor is heated. If the ignition switch is being ON, it may indicate lower than normal intake temperature.
Coolant
This parameter displays the temperature of the engine coolant as calculated by the ECM using the signal input from the engine coolant temperature (ECT) sensor. The Tech 2 will display a low temperature when signal voltage is high and a high temperature when the signal voltage is low.
Coolant Temperature
Sensor
Volts 0.4 - 0.6 0.4 - 0.6 This parameter displays the temperature of the engine coolant based on signal input from the engine coolant temperature (ECT) sensor to the ECM J1-27 terminal. The Tech 2 will display a low signal voltage when the temperature is high and a high signal voltage when the temperature is low.
Tech 2
This parameter displays the temperature of the fuel as calculated by the ECM using the signal input from the fuel temperature (FT) sensor. The Tech 2 will display a low temperature when signal voltage is high and a high temperature when the signal voltage is low.
Fuel Temperature
Sensor
Volts 0.7 - 2.3 0.7 - 2.3 This parameter displays the temperature of the fuel based on signal input from the fuel temperature (FT) sensor to the ECM J1-29 terminal. The Tech 2 will display a low signal voltage when the temperature is high and a high signal voltage when the temperature is low.
Barometric
This parameter displays the barometric pressure as calculated by the ECM using the signal input from the barometric pressure (BARO) sensor.
Barometric Pressure Sensor
Volts Nearly 2.3 Volts at sea level
Nearly 2.3 Volts at sea level
This parameter displays the voltage signal input to the ECM J1-18 terminal from barometric pressure (BARO) sensor. BARO sensor is a range of values indicating a low voltage where in high altitude area.
MAF (Mass Air Flow)
This parameter displays the mass air flow into the engine as calculated by the ECM using the signal input from the mass air flow (MAF) sensor.
MAF (Mass Air Flow) Sensor
This parameter displays the voltage signal input to the ECM J1-40 terminal form the mass air flow (MAF) sensor. The Tech 2 will displays a high value at higher engine speeds, and a low value at low engine speed.
Accelerator Pedal Position
% 0 10 - 15 This parameter displays the angle of the accelerator pedal as calculated by the ECM using the signal input from the accelerator pedal position sensors. The APP indicated angle is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.
APP Sensor 1 (Accelerator Pedal Position)
Volts 0.1 - 1.2 1.1 - 1.3 This parameter displays the voltage signal input to the ECM J2-12 terminal from the accelerator pedal position (APP) sensor 1 of the APP sensor assembly.
APP sensor 1 is a range of values indicating a low voltage when the accelerator pedal is not depressed to a high voltage when the accelerator pedal is fully depressed.
APP Sensor 2 (Accelerator Pedal Position)
Volts 3.8 - 4.8 3.6 - 3.8 This parameter displays the voltage signal input to the ECM J2-10 terminal from the accelerator pedal position (APP) sensor 2 of the APP sensor assembly.
APP sensor 2 is a range of values indicating a high voltage when the accelerator pedal is not depressed to a low voltage when the accelerator pedal is fully depressed.
APP Sensor 3 (Accelerator Pedal Position)
Volts 3.8 - 4.8 3.7 - 3.9 This parameter displays the voltage signal input to the ECM J2-8 terminal from the accelerator pedal position (APP) sensor 3 of the APP sensor assembly.
APP sensor 3 is a range of values indicating a high voltage when the accelerator pedal is not depressed to a middle voltage when the accelerator pedal is fully depressed.
Desired Intake
This parameter displays intake throttle valve position desired by the ECM based on current driving conditions.
Tech 2
% -3 - 3 -3 - 3 This parameter displays difference of actual and desired value (actual intake throttle – desired intake throttle). This can be used determine sensor accuracy or intake throttle valve problems.
ITP Sensor
This parameter displays the voltage signal input to the ECM J1-57 terminal from the intake throttle position sensor of the intake throttle valve. Intake throttle position sensor is a range of values indicating a low voltage when the intake throttle valve is closed to a high voltage when the intake throttle valve is opened.
Intake Throttle Duty Cycle
% 10 - 30 10 - 30 This parameter displays the intake throttle valve control duty signal from the ECM J1-56 terminal. When the small duty signal, the intake throttle valve is controlled to close. When the large duty signal, the intake throttle valve is controlled to open.
Desired EGR
This parameter displays EGR valve position desired by the ECM based on current driving condition.
EGR Position Difference
% -3 - 3 -3 - 3 This parameter displays difference of actual and desired value (actual EGR position – desired EGR position). This can be used determine sensor accuracy or EGR valve problems.
EGR Position
This parameter displays the voltage signal input to the ECM J1-32 terminal from the EGR position sensor of the EGR valve. EGR position sensor is a range of values indicating a low voltage when the EGR valve is closed to a high voltage when the EGR valve is opened.
EGR Motor Duty Cycle
% 10 - 30 10 - 30 This parameter displays the EGR valve control duty signal from the ECM J1-63 terminal. When the small duty signal, the EGR valve is controlled to close.
When the large duty signal, the EGR valve is controlled to open.
Desired Fuel Rail Pressure
This parameter displays fuel rail pressure desired by the ECM based on current driving condition.
This parameter displays difference of actual and desired value (actual rail pressure – desired fuel rail pressure). This can be used determine sensor accuracy or fuel pressure problems.
Fuel Rail Pressure Sensor
Volts 1.4 - 1.5 2.2 - 2.5 This parameter displays the voltage signal input to the ECM J1-48 and J1-68 terminals from fuel rail pressure (FRP) sensor. FRP sensor is a range of values indicating a low voltage when the fuel rail pressure is low to a high voltage when the fuel rail pressure is high.
SCV Current mA 1700 - 2000 1600
-2000
This parameter displays the suction control valve (SCV) control feedback current input to the ECM J1-50 and J1-70 terminals from the SCV. When the low current is supplied, the SCV is controlled to open (fuel supply to the fuel rail is increased). When the high current is supplied, the SCV is controlled to close (fuel supply to the fuel rail is reduced).
SCV Duty Cycle % 40 - 45 35 - 45 This parameter displays the suction control valve (SCV) control duty signal from the ECM J1-50 and J1-70 terminals. When the small duty signal, the SCV is controlled to open (fuel supply to the fuel rail is increased). When the large duty signal, the SCV is controlled to close (fuel supply to the fuel rail is reduced).
Tech 2
mm3/st 6 - 12 9 - 13 This parameter displays a total injection quantity (main injection quantity + pre injection quantity) desired by the ECM based on current driving conditions.
Main Injection Quantity
mm3/st 3 - 8 7 - 10 This parameter displays a main injection quantity desired by the ECM based on current driving conditions.
Pre Injection Quantity
mm3/st 3 - 4 2 - 3 This parameter displays a pilot injection quantity desired by the ECM based on current driving conditions.
Cylinder 1 Compensation
mm3/st -5.0 - 5.0 (Varies)
0 This parameter displays the adjustment of fuel volume for cylinder 1 at low engine speed area (from idle to around 1800RPM) as calculated by the ECM.
When the compensation volume is negative, the fuel volume is reducing. When the compensation volume is positive, the fuel volume is increasing. If there is a cylinder that is excessively high or low, it may indicate faulty fuel injector, weak or slightly seized cylinder.
Cylinder 2 Compensation
mm3/st -5.0 - 5.0 (Varies)
0 This parameter displays the adjustment of fuel volume for cylinder 2 at low engine speed area (from idle to around 1800RPM) as calculated by the ECM.
When the compensation volume is negative, the fuel volume is reducing. When the compensation volume is positive, the fuel volume is increasing. If there is a cylinder that is excessively high or low, it may indicate faulty fuel injector, weak or slightly seized cylinder.
Cylinder 3 Compensation
mm3/st -5.0 - 5.0 (Varies)
0 This parameter displays the adjustment of fuel volume for cylinder 3 at low engine speed area (from idle to around 1800RPM) as calculated by the ECM.
When the compensation volume is negative, the fuel volume is reducing. When the compensation volume is positive, the fuel volume is increasing. If there is a cylinder that is excessively high or low, it may indicate faulty fuel injector, weak or slightly seized cylinder.
Cylinder 4 Compensation
mm3/st -5.0 - 5.0 (Varies)
0 This parameter displays the adjustment of fuel volume for cylinder 4 at low engine speed area (from idle to around 1800RPM) as calculated by the ECM.
When the compensation volume is negative, the fuel volume is reducing. When the compensation volume is positive, the fuel volume is increasing. If there is a cylinder that is excessively high or low, it may indicate faulty fuel injector, weak or slightly seized cylinder.
Main Injection Base Pulse
Width
micro sec 600 - 800 400 - 550 This parameter displays the time the ECM turns ON the fuel injectors. The Tech 2 will display a higher value with a longer pulse width, or a lower value with a shorter pulse width.
Main Injection Start
°CA 2 - 5 4 - 8 This parameter displays the main injection timing calculated by the ECM based on the crankshaft position (CKP) sensor and camshaft position (CMP) sensor inputs using a target injection timing map. This timing is compensated by engine coolant temperature, altitude and intake air temperature, etc.
Pre Injection Interval
°CA 17 - 23 11 - 17 This parameter displays the injection interval between end of pilot injection and start of main injection calculated by the ECM based on current driving condition.
Rail Pressure
This parameter displays the state of the fuel rail pressure feedback to the ECM.
“Wait Mode” indicates the ignition switch is turned ON position. “Feedback Mode” indicates the engine is during crank or run. “Shutoff Mode” indicates the ignition switch is turned OFF position or immobilizer system is activating.
“Restart Mode” indicates the ignition switch continues being OFF position from
“Shutoff Mode”.
Tech 2 Parameter
Units Displayed
At Engine Idle
At Engine 2000RPM
Definitions
Engine Mode Halt Mode / Wait Mode / Crank Mode /
Fuel Mode
Fuel Mode Fuel Mode This parameter displays the state of engine. Wait Mode” indicates the ignition switch is turned ON position. “Crank Mode” indicates the engine is during crank.
“Fuel Mode” indicates the engine is run. “Halt Mode” indicates the ignition switch is tuned OFF position.
Synchronization Mode
0 / 1 / 2 2 2 This parameter displays the synchronization state of the crankshaft position (CKP) sensor signal and camshaft position (CMP) sensor signal. The Tech 2 will display “0”, “1” or “2”. “0” indicates the CMP sensor signal is not detected or only CKP sensor signal is detected. “1” indicates CMP sensor signal is detected but CKP sensor signal is not detected. “2” indicates both sensor signals are detected correctly.
Supply Pump Difference Learned Value
0 / 2 0 / 2 0 This parameter displays the characteristic learning state of the fuel supply pump. The Tech 2 will display “0” or “2”. “2” indicates the learning conditions are met during idle speed after warm-up. “0” indicates the learning conditions are not met.
Immobilizer Signal
Received / Not Received
Received Received This parameter displays the state of the response signal to the ECM J2-62 terminal. The Tech 2 will display Received or Not Received. “Received”
indicates the response signal from the immobilizer control unit (ICU) is received.
Wrong Immobilizer Signal Received
Received / Not Received
Not Received
Not Received
This parameter displays the state of the received response signal to the ECM J2-62 terminal. The Tech 2 will display Received or Not Received. “Received”
indicates the received response signal from the immobilizer control unit (ICU) is not agreed with calculation in the ECM.
Immobilizer Function Programmed
Yes / No Yes Yes This parameter displays the state of the immobilizer function programming in the ECM. The Tech 2 will display Yes or No. “Yes” indicates the security code &
secret key is correctly programmed in the ECM. “No” indicates the ECM is not programmed or ECM is reset.
Security Wait Time
Active (Time) / Inactive
Inactive Inactive This parameter displays the state of the security guard in the ECM. The Tech 2 will display Active (Time) or Inactive. “Active (Time)” indicates the ECM is under security guard, ignition switch must be being ON certain time to return
“Inactive”. If the replacement ECM is applied from other vehicle without reset ECM, “Active (Time)” may be indicated.