Fuel Pump Test - Code 22
- Turn ignition switch to the "ON" position and listen to the fuel pump operating sound. The sound must be heard for about 5 seconds.
- On Maxima and 300ZX if sound was heard, go to step 3). If sound was not heard, check fuel pump relay and fuse. Check for continuity between terminals No. 1 and 2 of relay connector, and for insulation between terminals 3 and 4. See Fig 1 . If not good, replace fuel pump relay. If okay, check harness between ECU and fuel pump, and harness between fuel pump and fuse block. If harness is defective, replace/repair. If harness is okay, go to step 4).
- Disconnect ECCS 15-pin connector, and check voltage between terminal No. 108 and ground when ignition switch is turned to "ON". See Fig 2 . Battery voltage should be present. If not, check harness, and replace or repair as necessary.
- Check fuel pump for continuity between leads of fuel pump connector. On Maxima and 300ZX, also check pump connector terminals for insulation. If not okay, replace fuel pump. If okay, replace ECU on Maxima and 300ZX.
- Turn ignition switch to "ON". Check voltage between fuel pump harness connector terminal D and ground. Battery voltage should exist for 5 seconds after turning ignition switch to "ON". If okay, go to next step. If not okay, check harness continuity between fuel pump and ground, fuel pump relay, and power source to the ECU.
- Check ground circuit. Turn ignition switch to "OFF". Disconnect fuel pump harness connector. Check resistance between terminal E and ground. No resistance should exist. Disconnect fuel pump harness connector, and check resistance between terminals D and E. No resistance should be present. If not okay, replace fuel pump. If okay, check crank angle sensor circuit, and test again if it is necessary.