DIAGNOSIS
TEST 37
CAN 2 signal (interface) Flash code: 4x long, 4x short
Error location (hex): C4
Error display: Yes (indicator light EDC on, or shown in display) Error path: CAN signal to pump control unit on switching on
Effect of error: Engine goes into fast idling (ca. 750 rpm), acceleration now impossible Possible
cause of error: Interface error
Injection pump (pump control unit) faulty
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 38
Shutdown via quantity solenoid valve (after-run test) Flash code: 4x long, 5x short
Error location (hex): C5
Error display: Yes (indicator light EDC on, or shown in display)
Error path: Status of solenoid valve shutdown (MAB) in after-running Effect of error: Final engine speed reduced to 2200 rpm
Full load quantity reduced by 25 – 40%,
impossible to shutdown engine via MAR (high-pressure solenoid valve in injection pump)
Possible Actuation of control unit is faulty (engine control unit defective) cause of error: Injection pump (pump control unit) faulty
Road speed signal implausible
Note 1: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Note 2: In the event of errors in after-running, the road speed signal must also be checked.
Reason: If the road speed transducer already shows 0 km/h when the vehicle is rolling and the ignition is then switched off, there is after-running.
The various shutdown paths in after-running can then be classified as defective because the speed does not drop away fast enough (vehicle is rolling).
Condition for testing: Diagnostics connector box (test box) connected
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Injection pump – – – − Delete error memory
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 39
Busoff: CAN 1 signal Flash code: 4x long, 6x short
Error location (hex): 46
Error display: Yes (indicator light EDC on, or shown in display) Error path: Vehicle CAN (busoff)
Possible
cause of error: Interruption on line, short-circuit, control unit faulty
Note 1: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Note 2: The CAN databus is described in the repair manual T 51 Condition for testing: Diagnostics connector box (test box) connected
Ignition switched off
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Engine control
unit Resistance measurement at diagnostics control box between Pin B11 and B12 Target value: ∼120 Ω
− Test lines
− Test plug connectors
− At ca. 0 Ω short-circuit from CAN-H to CAN-L
− Try replacing the control unit
DIAGNOSIS
TEST 40
Pump speed sensor (IWZ signal) Flash code: 4x long, 7x short
Error location (hex): C7
Error display: Yes (indicator light EDC on, or shown in display) Error path: Fuel system
Fuel injection pump Effect of error: Engine shuts down Function: Refer to page 3.02 - 14
Possible Fault in fuel system (leak, clogged, air in system)
cause of error: Injection pump defective (dynamic: implausible, static; increments per segment not complete)
Note 1: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Note 2: The fuel system layout (low pressure) is shown in the repair manuals A 13 and A 14.
Test Measurement Remedy
Fuel system Fuel pressure − Vent (filter, then injector line at at least 3 injection nozzles)
− After successful start, leave engine idling for at least 30 s
− Fill the tank
Injection pump – – – − Test pump installation*
− Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 41
Residual quantity Flash code: 4x long, 8x short
Error location (hex): C8
Error display: Yes (indicator light EDC on, or shown in display)
Error path: CAN signal (quantity that is transferred to the pump on the CAN-bus) Effect of error: Engine stops because calculation of quantities inaccurate
Function: If despite the quantity "quantity 0" being specified on the CAN the speed is
>700 rpm, the boost pressure >300 mbar and NBF signals (only with level 1) are detected, there is classification as an error
Possible Line interruption, short-circuit, control unit defective, NBF (only in level 1) faulty, cause of error: intake manifold pressure sensor faulty
Note: Before any replacement of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
Intake manifold
pressure sensor See test 4 − See test 4 Needle movement
sensor See test 14 − See test 14
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 42
Pump control unit self-test: solenoid valve output stage Flash code: 4x long, 9x short
Error location (hex): C9
Error display: Yes (indicator light EDC on, or shown in display)
Error path: Hardware error in solenoid valve output stage (pump control unit) Effect of error: None known of
Function: Checking of output stage in PSG self-test Possible
cause of error: Pump control unit (injection pump) faulty
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 43
Injection timing device (pump control unit) Flash code: 4x long, 10x short
Error location (hex): CA
Error display: Yes (indicator light EDC on, or shown in display)
Error path: Target-actual value exceeding/not reaching injection timing device Effect of error: Final engine speed reduced to 1700 rpm
Full load quantity reduced by 50 – 60%
Possible Line interruption, short-circuit cause of error: Fault in fuel low-pressure system
– faulty or wrong overflow valve – air or leaks in the system – faulty pre-supply pump – blocked filters
– clogged lines – empty fuel tank – faulty injection pump – faulty fuel filter
Note 1: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Note 2: The fuel pipework layout (low pressure) is shown in the repair manuals A 13 and A 14.
Test Measurement Remedy
Injection pump Error condition:
In case of deviation of target from actual value for injection start by more than
+/– 3 grad longer than 8 s and speed > 1200 rpm
− Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
Fuel system Fuel pressure − See above (possible cause of error)
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 44
Timeout: CAN signal PSG 1 Flash code: 4x long, 11x short
Error location (hex): CB
Error display: Yes (indicator light EDC on, or shown in display)
Error path: CAN signal from pump control unit to engine control unit (timeout) Effect of error: Engine goes into increased idling speed
Possible
cause of error: Line interruption, short-circuit, control unit faulty, injection pump faulty
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Condition for testing: Diagnostics connector box (test box) connected Ignition switched off
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Engine control
unit Resistance measurement at diagnostics control box between Pin A27 and A24 Target value: ∼120 Ω
− Test lines
− Test plug connectors
− At ca. 0 Ω short-circuit from CAN-H to CAN-L
− If fault is still present, try replacing the control unit
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 45
Shutdown via voltage monitoring (after-running test) Flash code: 4x long, 12x short
Error location (hex): 99
Error display: Yes (indicator light EDC on, or shown in display) Error path: Status shutdown via voltage monitoring)
Effect of error: Final engine speed reduced to 2200 rpm Torque reduced by 25 – 40%,
shutdown via voltage monitoring impossible
Function: In after-running, an error is consciously simulated (limit values). If the expected fall in speed does not come about, it is classified as an error.
Possible Line interruption between engine control unit and injection pump (pump control unit), cause of error: engine control unit faulty, injection pump (pump control unit) faulty
If additionally the error "Plausibility shutdown signal (MAB)" or "Shutdown via monitoring module" occurs, check MAB line.
Note 1: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Note 2: In the event of errors in after-running, the road speed signal must also be checked.
Reason: If the road speed transducer already shows 0 km/h when the vehicle is rolling and the ignition is then switched off, there is after-running. The various shutdown paths in after-running can then be classified as defective because the speed does not drop away fast enough (vehicle is rolling).
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Engine control unit – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the engine control unit
Pump control unit
(injection pump) – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
DIAGNOSIS
TEST 46
Timeout: CAN signal MSG 1 Flash code: 4x long, 13x short
Error location (hex): B1
Error display: Yes (indicator light EDC on, or shown in display)
Error path: CAN signal from engine control unit to pump control unit (timeout) Effect of error: Final engine speed reduced to 2000 rpm
Torque reduced by 25 – 40%
Possible
cause of error: Line interruption, short-circuit, control unit faulty, injection pump faulty
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Condition for testing: Diagnostics connector box (test box) connected Ignition switched off
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Engine control
unit Resistance measurement at diagnostics control box between Pin A27 and A24 Target value: ∼120 Ω
− Test lines
− Test plug connectors
− At ca. 0 Ω short-circuit from CAN-H to CAN-L
− If fault is still present, try replacing the control unit
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 47
Supply voltage, pump control unit Flash code: 4x long, 14x short
Error location (hex): B3
Error display: Yes (indicator light EDC on, or shown in display)
Error path: Power supply to pump control unit, relay, redundant shutdown (MAR) Effect of error: Engine shuts down
Engine does not start Possible
cause of error: Line interruption, short-circuit Condition for testing: See below
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Power supply Voltage measurement at cable loom plug to PSG between Pin 7 (+) and Pin 6 (–) Target value: UBat
Error limits: U < 7 V or U > 32 V
− Test line
− Test plug connection
Relay redundant
shutdown (MAR) Switch on ignition
Voltage measurement at diagnostics connector box (test box) between Pin B18 and Pin B1
Target value: UBat
Switch off ignition
Disconnect engine control unit
Resistance measurement at diagnostics control box between Pin B18 and Pin B1 Target value: 180 – 250 Ω
− Test line
− Test plug
− Replace relay (MAR)
Plug for pump control unit
DIAGNOSIS
TEST 48
CAN signal, pump control unit (interface) Flash code: 4x long, 15x short
Error location (hex): B4
Error display: Yes (indicator light EDC on, or shown in display)
Error path: CAN signal to pump control unit (timeout value range violation) Effect of error: Engine goes into increased idling speed
Engine shuts down
Possible Line interruption, short-circuit, control unit faulty, injection pump faulty, cause of error: engine speed sensor flywheel faulty
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Condition for testing: Diagnostics connector box (test box) connected Ignition switched off
Follow vehicle-related wiring diagrams
Test Measurement Remedy
Engine control unit Resistance measurement at diagnostics control box between Pin A27 and A24 Target value: ∼120 Ω
− Test lines
− Test plug connectors
− At ca. 0 Ω short-circuit from CAN-H to CAN-L
− If fault still present, try replacing control unit
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
Engine speed
sensor See test 3 − See test 3
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 49
Speed sensor signal detection, pump control unit Flash code: 5x long, 1x short
Error location (hex): B7
Error display: Yes (indicator light EDC on, or shown in display) Error path: Engine speed signal to the pump control unit Effect of error: Final engine speed reduced to 1800 rpm
Torque reduced by 25 – 40%
Function: Monitoring on negative flank in data collection window
Possible Speed sensor flywheel faulty, sensor distance false (target: 0.5 – 1.5 mm).
cause of error: Control unit faulty, injection pump installation wrong, injection pump faulty.
"Injection start deviation" is sometimes displayed when there is a loose contact.
The error "Speed sensor at flywheel" often appears at the same time
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Engine speed
sensor See test 3 − See test 3
Injection pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
Cables Line between Pin A35 engine control unit and Pin 8 pump control unit
− Test lines
− Test plug connectors
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 50
Pump control unit self-test: EEPROM checksum Flash code: 5x long, 2x short
Error location (hex): B5
Error display: Yes (indicator light EDC on, or shown in display) Error path: Checksum test EEPROM
Effect of error: Final engine speed reduced to 1700 rpm Torque reduced by 50 – 60%,
as injection timing device can go to advance stop Function: Checksum test in self-test
Possible
cause of error: Control unit faulty, pump control unit (injection pump) defective
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Fuel injection
pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 51
Pump control unit self-test: EEPROM status Flash code: 5x long, 3x short
Error location (hex): B6
Error display: Yes (indicator light EDC on, or shown in display) Error path: Status check EEPROM (hardware error)
Effect of error: Final engine speed reduced to 1700 rpm Torque reduced by 50 – 60%,
as injection timing device can go to advance stop Function: Hardware check in self-test
Possible
cause of error: Control unit faulty, pump control unit (injection pump) defective
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy Fuel injection
pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 52
Pump control unit self-test: ADC status Flash code: 5x long, 4x short
Error location (hex): B2
Error display: Yes (indicator light EDC on, or shown in display) Error path: Status analog-digital converter
Effect of error: Final engine speed reduced to 2000 rpm Torque reduced by 25 – 40%
Function: In the self-test checking earth potential of a channel of the AD converter there is no quantity correction
Solenoid valve voltage is no longer acquired Possible
cause of error: Control unit faulty, injection pump defective
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Fuel injection
pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 53
Pump control unit self-test: RAM Flash code: 5x long, 5x short
Error location (hex): B9
Error display: Yes (indicator light EDC on, or shown in display) Error path: RAM in pump control unit
Effect of error: Engine does not start Function: Checking RAM in self-test Possible
cause of error: Control unit faulty, injection pump defective
Note: Before any exchange of pump or control units the error memory should always be deleted and the error observed.
If there are a number of error entries, the corresponding test instructions should generally only be taken into account where they do not require a change of pump or control unit.
Test Measurement Remedy
Fuel injection
pump – – – − Delete error memory
− Read error memory once again
− If fault still present, try replacing the injection pump*
* Fitting and removing the injection pump and carrying out the associated adjustments is described in repair manuals A 13 and A 14!
DIAGNOSIS
TEST 54
Polarity reversal, speed sensor on flywheel Flash code: 5x long, 6x short
Error location (hex): 91
Error location (hex): 91