Diagnosis Procedure

FUEL PUMP CONTROL MODULE


Description






The Fuel pump control module (FPCM) adjusts the voltage supplied to the fuel pump to control the amount of fuel flow. When the FPCM increases the voltage supplied to the fuel pump, the fuel flow is increased. When the FPCM decreases the voltage, the fuel flow is decreased.




FUEL PUMP CONTROL MODULE


Diagnosis Procedure

1.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connections M16, M70. Power Supply and Ground Circuit.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace ground connections.
2.CHECK FPCM POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect fuel pump control module (FPCM) harness connector.
3. Turn ignition switch ON.





4. Check the voltage between FPCM harness connector and ground.





Is the inspection result normal?
YES - GO TO 4.
NO - GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors B4, E106
- IPDM E/R harness connector E8
- 15 A fuse (No. 81)
- Harness for open or short between FPCM and IPDM E/R
- Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK FPCM GROUND CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Check the continuity between FPCM harness connector and ground.





3. Also check harness for short to power.
Is the inspection result normal?
YES - GO TO 5.
NO - Repair open circuit or short to power in harness or connectors.
5.CHECK FPCM GROUND CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect "fuel level sensor unit and fuel pump" (main) harness connector.
2. Disconnect dropping resistor harness connector.
3. Check the continuity between "fuel level sensor unit and fuel pump" (main) harness connector or FPCM harness connector and dropping resistor harness connector.





4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 7.
NO - GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors B65, B434
- Harness for open or short between "fuel level sensor unit and fuel pump" (main) and dropping resistor
- Harness for open or short between FPCM and dropping resistor
- Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK FPCM INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check the continuity between FPCM harness connector and ECM harness connector.





3. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 9.
NO - GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors B2, M13
- Harness connectors F102, M72
- Harness for open or short between FPCM and ECM
- Repair open circuit, short to ground or short to power in harness or connectors.
9.CHECK FPCM OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between ECM and FPCM





2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 11.
NO - GO TO 10.
10.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors B2, M13
- Harness connectors F102, M72
- Harness for open or short between ECM and FPCM
- Repair open circuit, short to ground or short to power in harness or connectors.
11.CHECK FPCM
Component Inspection.
Is the inspection result normal?
YES - GO TO 12.
NO - Replace FPCM.
12.CHECK INTERMITTENT INCIDENT
Description.
- INSPECTION END