Fuel Pump: Testing and Inspection
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). If the fuel pump does not make noise, check as follows:
1. Turn the ignition switch to LOCK (0).
2. Remove PGM-FI main relay 2 (A) from auxiliary under-hood relay box A.
3. Turn the ignition switch to ON (II).
4. Measure the voltage between auxiliary under-hood relay box A 17P connector terminal No. 9 (PGM-FI main relay 2) and body ground.
Is there battery voltage?
YES -
Go to step 10.
NO -
Go to step 5.
5. Turn the ignition switch to LOCK (0).
6. Remove the fuse lid panel Fuse Lid Panel Removal / Installation.
7. Remove the cover from under-dash fuse/relay box connector B (36P).
8. Turn the ignition switch to ON (II).
9. Measure the voltage between under-dash fuse/relay box connector B (36P) terminal No. 22 and body ground.
Is there battery voltage?
YES -
Repair an open in the wire between PGM-FI main relay 2 and the under-dash fuse/relay box .
NO -
Replace the under-dash fuse/relay box; USA models Under-Dash Fuse/Relay Box Removal and Installation (USA Models), Canada models Under-Dash Fuse/Relay Box Removal and Installation (Canada Models).
10. Measure the voltage between auxiliary under-hood relay box A 17P connector terminal No. 1 (PGM-FI main relay 2) and body ground.
Is there battery voltage?
YES -
Go to step 12
NO -
Go to step 11.
11. Measure the voltage between under-dash fuse/relay box connector B (36P) terminal No. 19 and body ground.
Is there battery voltage?
YES -
Repair an open in the wire between PGM-FI main relay 2 and the under-dash fuse/relay box .
NO -
- Check the No. B20 FUEL PUMP (15 A) fuse in the under dash fuse/relay box.
- If the fuse is OK, replace the under-dash fuse/relay box; USA models Under-Dash Fuse/Relay Box Removal and Installation (USA Models), Canada models Under-Dash Fuse/Relay Box Removal and Installation (Canada Models).
12. Turn the ignition switch to LOCK (0).
13. Connect auxiliary under-hood relay box A 17P connector terminal No. 10 to body ground with a jumper wire.
14. Jump the SCS line with the HDS.
15. Disconnect ECM/PCM connector A (44P).
16. Check for continuity between ECM/PCM connector terminal A15 and body ground.
Is there continuity?
YES -
Go to step 17.
NO -
Repair an open in the wire between PGM-FI main relay 2 and the ECM/PCM (A15).
17. Reinstall PGM-FI main relay 2.
18. Connect ECM/PCM connector terminal A6 to body ground with a jumper wire.
19. Turn the ignition switch to ON (II).
20. Measure the voltage between ECM/PCM connector terminal A15 and body ground.
Is there battery voltage?
YES -
Go to step 21.
NO -
Replace PGM-FI main relay 2.
21. Turn the ignition switch to LOCK (0).
22. Reconnect ECM/PCM connector A (44P).
23. Remove the cover from the bottom of auxiliary under-hood relay box A. Turn the ignition switch to ON (II), and measure the voltage between auxiliary under-hood relay box A 17P connector terminal No. 10 (PGM-FI main relay 2) 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 with a known-good ECM/PCM, replace the original ECM/PCM Service and Repair.
NO -
Go to step 24.
24. Turn the ignition switch to LOCK (0).
25. Remove the rear tray.
26. Remove the access panel from the floor.
27. Disconnect the fuel tank unit 4P connector.
28. Turn the ignition switch to ON (II), and measure the voltage between fuel tank unit 4P connector terminal No. 1 and body ground within 2 seconds.
Is there battery voltage?
YES -
Go to step 29.
NO -
Go to step 31.
29. Turn the ignition switch to LOCK (0).
30. Check for continuity between fuel tank unit 4P connector terminal No. 3 and body ground .
Is there continuity?
YES -
Replace the fuel pump.
NO -
Repair an open in the wire between the fuel tank unit and G602.
31. Turn the ignition switch to LOCK (0).
32. Remove PGM-FI main relay 2 (A) from auxiliary under-hood relay box A.
33. Connect auxiliary under-hood relay box A 17P connector terminals No. 1 and No. 2 (PGM-FI main relay 2) with a jumper wire.
34. Turn the ignition switch to ON (II), and measure the voltage between fuel tank unit 4P connector terminal No. 1 and body ground.
Is there battery voltage?
YES -
Replace PGM-FI main relay 2.
NO -
Repair an open in the wire between PGM-FI main relay 2 and the fuel tank unit 4P connector. If the wire is OK, replace the under-dash fuse/relay box; USA models Under-Dash Fuse/Relay Box Removal and Installation (USA Models), Canada models Under-Dash Fuse/Relay Box Removal and Installation (Canada Models).