P1220

P1220 FUEL PUMP CONTROL MODULE (FPCM)





Description

SYSTEM DESCRIPTION





This system controls the fuel pump operation. The amount of fuel flow delivered from the fuel pump is altered between two flow rates by the FPCM operation. The FPCM determines the voltage supplied to the fuel pump
(and therefore fuel flow) according to the following conditions.






COMPONENT DESCRIPTION





The 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.




On Board Diagnosis Logic









DTC Confirmation Procedure

CAUTION:
Always drive vehicle at a safe speed.

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next step.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V with ignition switch ON.

WITH CONSULT-III
1. Turn ignition switch ON and select "DATA MONITOR" mode with CONSULT-III.
2. Make sure that "COOLANT TEMP/S" indicates less than 70�C (158�F). If not, cool down the engine.
3. Start engine.
4. Hold vehicle at the following conditions for 12 seconds.





5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to SEE Diagnosis Procedure.

WITH GST
Follow the procedure "WITH CONSULT-III" above.




Diagnosis Procedure
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Power Supply And Ground Circuit.





OK or NG
OK - GO TO 2.
NG - Repair or replace ground connections.
2.CHECK FPCM POWER SUPPLY CIRCUIT
1. Disconnect fuel pump control module (FPCM) harness connector.





2. Turn ignition switch ON.





3. Check voltage between FPCM terminal 4 and ground with CONSULT-III or tester.





OK or NG
OK - GO TO 3.
NG - Repair open circuit or short to ground or short to power in harness or connectors.
3.CHECK FPCM GROUND CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Check harness continuity between FPCM terminal 1 and ground. Refer to Wiring Diagram.





3. Also check harness for short to power.
OK or NG
OK - GO TO 4.
NG - Repair open circuit or short to power in harness or connectors.
4.CHECK FPCM GROUND CIRCUIT FOR OPEN AND SHORT-II





1. Disconnect "fuel level sensor unit and fuel pump" harness connector.
2. Disconnect dropping resistor harness connector.
3. Check harness continuity between the following;
"fuel level sensor unit and fuel pump" terminal 3 and dropping resistor terminal 2, FPCM terminal 2 and dropping resister terminal 2. Refer to Wiring Diagram.





4. Check harness continuity between the following;
FPCM terminal 2 and ground, "fuel level sensor and fuel pump" terminal 3 and ground. Refer to Wiring Diagram.





5. Also check harness for short to power.
OK or NG
OK - GO TO 6.
NG - GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors C1, E41
- Harness for open or short between "fuel level sensor unit and fuel pump" and dropping resistor
- Harness for open or short between FPCM and dropping resistor
- Harness for short between "fuel level sensor unit and fuel pump" and ground
- Harness for short between FPCM and ground
- Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK FPCM INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 38 and FPCM terminal 2. Refer to Wiring Diagram.





3. Check harness continuity between ECM terminal 38 and ground. Refer to Wiring Diagram.





4. Also check harness for short to power.
OK or NG
OK - GO TO 8.
NG - GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F32, E2
- Harness for open or short between ECM and FPCM
- Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK FPCM OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 39 and FPCM terminal 3. Refer to Wiring Diagram.





2. Also check harness for short to ground and short to power.
OK or NG
OK - GO TO 10.
NG - GO TO 9.
9.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F32, E2
- Harness for open or short between ECM and FPCM
- Repair open circuit or short to ground or short to power in harness or connectors.
10.CHECK FPCM
SEE Component Inspection.
OK or NG
OK - GO TO 11.
NG - Replace FPCM.
11.CHECK INTERMITTENT INCIDENT
How to Check Terminal and Intermittent Incident.
- INSPECTION END




Component Inspection

FUEL PUMP CONTROL MODULE (FPCM)





1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.





3. Check voltage between FPCM terminal 2 and ground under the following conditions.





4. If NG, replace fuel pump control module.