Fuel Pump Circuit: Wiring Diagram
DIAGNOSTIC PROCEDURE CHART
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK OPERATING SOUND OF FUEL PUMP. Make sure that the fuel pump operates for two seconds when turning the ignition switch to ON.
NOTE:
Fuel pump operation can also be executed using Subaru Select Monitor.
Regarding the procedures, refer to "Compulsory Valve Operation Check Mode". <Ref. to COMPULSORY VALVE OPERATION CHECK MODE . > |
Does the fuel pump emit operating sound? | Check the fuel injector circuit. <Ref. to FUEL INJECTOR CIRCUIT , Diagnostics for Engine Starting Failure .> |
Go to step 2 . |
2 CHECK GROUND CIRCUIT OF FUEL PUMP.
|
Is the resistance less than 5 Ω? | Go to step 3. | Repair the harness and connector.
NOTE:
In this case, repair the following item: Open circuit in harness between fuel pump connector and chassis grounding terminal
|
3 CHECK POWER SUPPLY TO FUEL PUMP.
|
Is the voltage 10 V or more? | Replace the fuel pump. <Ref. to FUEL PUMP . > | Go to step 4 . |
4 CHECK HARNESS BETWEEN FUEL PUMP AND FUEL PUMP RELAY CONNECTOR.
|
Is the resistance less than 1 Ω? | Go to step 5. | Repair the harness and connector.
NOTE:
In this case, repair the following item:
|
| 5 CHECK HARNESS BETWEEN FUEL PUMP AND FUEL PUMP RELAY CONNECTOR. Measure the resistance of harness between fuel pump and fuel pump relay connector. Connector & terminal (R58) No. 5 - Chassis ground: |
Is the resistance 1 MΩ or more? | Go to step 6. | Repair the short circuit of harness between fuel pump and fuel pump relay connector. |
6 CHECK FUEL PUMP RELAY.
|
Is the resistance less than 10 Ω? | Go to step 7. | Replace the fuel pump relay. <Ref. to FUEL PUMP . > |
7 CHECK HARNESS BETWEEN ECM AND FUEL PUMP RELAY CONNECTOR.
|
Is the resistance less than 1 Ω? | Go to step 8. | Repair the open circuit of harness between ECM and fuel pump relay connector. |
| 8 CHECK POOR CONTACT. Check for poor contact of the ECM connector. |
Is there poor contact in ECM connector? | Repair poor contact of the ECM connector. | Check the fuel injector circuit. <Ref. to FUEL INJECTOR CIRCUIT , Diagnostics for Engine Starting Failure .> |