DTC Diagnosis Procedure
- CHECK FUEL PUMP RELAY POWER SUPPLY
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Turn ignition switch ON.
- Check the voltage between ECM harness connector terminals.
ECM
Voltage
Connector
+
Connector
-
Terminal
Terminal
F79
93
E77
152
Battery voltage
Is the inspection result normal?
YES
GO TO 3.
NO
GO TO 2.
- CHECK FUEL PUMP RELAY POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect IPDM E/R harness connector.
- Check the continuity between ECM harness connector and IPDM E/R harness connector.
+
-
Continuity
ECM
IPDM E/R
Connector
Terminal
Connector
Terminal
F79
93
E122
46
Existed
- Also check harness for short to ground.
Is the inspection result normal?
YES
Perform the trouble diagnosis for power supply circuit. Refer to DTC Diagnosis Procedure .
NO
Repair or replace error-detected parts.
- CHECK FPCM POWER SUPPLY
- Turn ignition switch OFF.
- Disconnect FPCM harness connector.
- Turn ignition switch ON.
- Check the voltage between FPCM harness connector and ground.
+
-
Voltage
FPCM
Connector
Terminal
C12
1
Ground
Battery voltage
Is the inspection result normal?
YES
GO TO 5.
NO
GO TO 4.
- CHECK FPCM POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect IPDM E/R harness connector.
- Check the continuity between FPCM harness connector and IPDM E/R harness connector.
+
-
Continuity
FPCM
IPDM E/R
Connector
Terminal
Connector
Terminal
C12
1
E124
13
Existed
- Also check harness for short to ground.
Is the inspection result normal?
YES
Perform the trouble diagnosis for power supply circuit. Refer to DTC Diagnosis Procedure .
NO
Repair or replace error-detected parts.
- CHECK FPCM GROUND CIRCUIT
- Turn ignition switch OFF.
- Check the continuity between FPCM harness connector and ground.
+
-
Continuity
FPCM
Connector
Terminal
C12
4
Ground
Existed
Is the inspection result normal?
YES
GO TO 6.
NO
Repair open circuit or short to power in harness or connectors.
- CHECK FPCM INPUT AND OUTPUT CIRCUIT
- Disconnect ECM harness connector.
- Check the continuity between FPCM harness connector and ECM harness connector.
+
-
Continuity
FPCM
ECM
Connector
Terminal
Connector
Terminal
C12
3
E77
130
Existed
2
136
- Also check harness for short to ground and to power.
Is the inspection result normal?
YES
GO TO 7.
NO
Repair or replace error-detected parts.
- CHECK FUEL PUMP CONTROL CIRCUIT
- Disconnect fuel level sensor unit and fuel pump harness connector.
- Check the continuity between FPCM harness connector and fuel level sensor unit and fuel pump harness connector.
+
-
Continuity
FPCM
Fuel level sensor unit and fuel pump
Connector
Terminal
Connector
Terminal
C12
6
C37
1
Existed
5
3
- Also check harness for short to ground and to power.
Is the inspection result normal?
YES
GO TO 8.
NO
Repair or replace error-detected parts.
- CHECK LOW PRESSURE FUEL PUMP
Refer to Component Inspection (Low Pressure Fuel Pump) .
Is the inspection result normal?
YES
GO TO 9.
NO
Replace fuel level sensor unit and fuel pump. Refer to Removal and Installation - VK56VD .
- CHECK FPCM
Refer to Component Inspection (FPCM) .
Is the inspection result normal?
YES
Check intermittent incident. Refer to Intermittent Incident .
NO
Replace FPCM. Refer to Removal and Installation .