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Fuel Pump Circuit Troubleshooting




Fuel Pump Circuit Troubleshooting

If you suspect a problem with the fuel pump, check that the fuel pump actually runs; when it is on, you will hear some noise if you listen to the fuel fill port with the fuel fill cap removed. The fuel pump should run for 2 seconds when the ignition switch is turned to ON (II), or press the engine start/stop button to select the ON mode. If the fuel pump does not make noise, check as follows:

1. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

2. Remove the driver's dashboard undercover Driver's Dashboard Undercover Removal / Installation.

3. Remove PGM-FI main relay 2 (A) from the driver's under-dash fuse/relay box.





4. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

5. Measure the voltage between PGM-FI main relay 2 4P connector terminal No. 4 and body ground.





Is there battery voltage?

YES -

Go to step 13.

NO -

Go to step 6.

6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

7. Remove PGM-FI main relay 1 (A) and the ETCS control relay (B) from the under-hood fuse/relay box.





8. Jump the SCS line with the HDS.

9. Disconnect the engine wire harness 13P connector (C101).

10. Disconnect driver's under-dash fuse/relay box connector F (33P).

11. Connect PGM-FI main relay 1 4P connector terminal No. 2 to body ground with a jumper wire.






12. Check for continuity between driver's under-dash fuse/relay box connector F (33P) terminal No. 31 and body ground.





Is there continuity?

YES -

Replace the driver's under-dash fuse/relay box Drivers Under-Dash Fuse/Relay Box (Drivers MICU) Removal and Installation.

NO -

- Repair open in the wire between the under-hood fuse/relay box and the driver's under-dash fuse/relay box.
- If the wire is OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.

13. Measure the voltage between PGM-FI main relay 2 4P connector terminal No. 2 and body ground.





Is there battery voltage?

YES -

Go to step 14.

NO -

- Check the No. 9 FUEL PUMP (20 A) fuse in the driver's under-dash fuse/relay box.
- If the fuse is OK, replace the driver's under-dash fuse/relay box Drivers Under-Dash Fuse/Relay Box (Drivers MICU) Removal and Installation.

14. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

15. Connect PGM-FI main relay 2 4P connector terminal No. 3 to body ground with a jumper wire.






16. Jump the SCS line with the HDS.

17. Disconnect ECM/PCM connector A (49P).

18. Check for continuity between ECM/PCM connector terminal A11 and body ground.





Is there continuity?

YES -

Go to step 19.

NO -

Repair open in the wire between PGM-FI main relay 2 and the ECM/PCM (A11).

19. Reinstall PGM-FI main relay 2.

20. Connect ECM/PCM connector terminal A6 to body ground with a jumper wire.





21. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

22. Measure the voltage between ECM/PCM connector terminal A11 and body ground.





Is there battery voltage?

YES -

Go to step 23.

NO -

Replace PGM-FI main relay 2.

23. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

24. Reconnect ECM/PCM connector A (49P).

25. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and measure the voltage between driver's under-dash fuse/relay box connector F (33P) terminal No. 22 and body ground within 2 seconds.





Is there battery voltage?

YES -

Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away and the ECM/PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.

NO -

Go to step 26.

26. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and measure the voltage between driver's under-dash fuse/relay box connector F (33P) terminal No. 22 and body ground after 2 seconds.





Is there battery voltage?

YES -

Go to step 27.

NO -

Replace the driver's under-dash fuse/relay box Drivers Under-Dash Fuse/Relay Box (Drivers MICU) Removal and Installation.

27. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

28. Remove the rear seat cushion Rear Seat Removal / Installation.

29. Remove the access panel from the floor; without SH-AWD Fuel Tank Unit Removal/Installation, with SH-AWD Fuel Tank Unit Removal/Installation.

30. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and measure the voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.





Is there battery voltage?

YES -

Go to step 35.

NO -

Go to step 31.

31. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

32. Remove PGM-FI main relay 2.

33. Connect PGM-FI main relay 2 4P connector terminals No. 1 and No. 2 with a jumper wire.






34. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and measure the voltage between fuel tank unit 4P connector terminal No. 2 and body ground.





Is there battery voltage?

YES -

Replace PGM-FI main relay 2.

NO -

- Repair open in the wire between the driver's under-dash fuse/relay box (D10) and the fuel tank unit4Pconnector.
- If the wire is OK, replace the driver's under-dash fuse/relay box Drivers Under-Dash Fuse/Relay Box (Drivers MICU) Removal and Installation.

35. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

36. Check for continuity between fuel tank unit 4P connector terminal No. 4 and body ground.





Is there continuity?

YES -

Replace the fuel pump Fuel Pump/Fuel Gauge Sending Unit Replacement.

NO -

Repair open in the wire between the fuel tank unit 4P connector and G602; without SH-AWD, with SH-AWD.