Fuel Pump Control System (G35)
- Turn ignition switch to ON position. Pinch fuel hose (at filter outlet) with fingers. For 5 seconds after ignition is turned on, pulsation should be felt on fuel hose. If pulsation is felt, system is operating normally. If pulsation is not felt, go to next step.
- Turn ignition switch to OFF position. Disconnect ECM harness connector. Turn ignition switch to ON position. Using or voltmeter, check for voltage between and ground and ECM harness connector terminal No. 23. See Fig 1. If battery voltage does not exist, go to next step. If battery voltage exists go to step 5
- Turn ignition switch to OFF position. Disconnect Intelligent Power Distribution Module - Engine Room (IPDM E/R) harness connector. Turn ignition switch to ON position. Using CONSULT-II or voltmeter, check for voltage between and ground and IPDM E/R harness connector E7 terminal No. 20. See Fig 2. If battery voltage exists, go to step 13. If battery voltage does not exist, go to next step.
- Check the following:
- Check harness connectors E108 and M15.
- Check harness connectors M72 and F102.
- Check for open or short between ECM and IPDM E/R.
Repair wiring and/or harness connectors as necessary. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
- Turn ignition switch to OFF position. Ensure all harness connectors are reconnected. Disconnect condenser harness connector. Turn ignition switch to ON position. Using CONSULT-II or voltmeter, check for voltage between and ground and condenser harness connector terminal No. 1. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Battery voltage should exist for one second after ignition switch is turned to ON position. Also check harness for short to ground or short to voltage. If problem is found, go to next step. If no problem is found, go to step 9.
- Turn ignition switch to OFF position. Remove and inspect 15-amp fuse at IPDM E/R, located at right rear corner of engine compartment. If necessary, replace fuse. If no problem is found or fuse is replaced, go to next step.
- Disconnect IPDM E/R harness connector E7. Check for continuity in Black/Yellow wire between condenser connector terminal No. 1 and IPDM E/R harness connector terminal No. 23. See Fig 2. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Also check harness for short to ground or short to battery voltage. If problem is found, go to next step. If no problem is found, go to step 13.
- Inspect in-line harness connectors between condenser connector terminal No. 1 and IPDM E/R for damage or proper connection. Check harness for short to ground or short to battery voltage. Repair or replace as necessary. After repair, recheck system for proper operation.
- Check for continuity between ground and condenser harness connector terminal No. 2. Also check harness for short to battery voltage. Repair or replace as necessary. If no problem is found, go to next step.
- Turn ignition switch to OFF position. Using an ohmmeter, measure resistance between condenser terminals No. 1 and 2. Resistance should be 1,000 ohms at 77°F (25°C). If results are as specified, go to next step. If results are not as specified, replace condenser. After repair, check system for proper operation.
- Turn ignition switch to OFF position. Disconnect fuel level sensor unit and fuel pump harness connector, located at top of fuel tank. Check Black/Yellow wire between in-line harness connector B2 terminal No. 18 and fuel level sensor unit and fuel pump harness connector terminal No. 1. See Fig 3. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Continuity should exist. Also check harness for short to ground or short to battery voltage. If no problem is found, go to next step. If problem is found, report open or short circuit(s) as necessary. After repair, check system for proper operation.
- Turn ignition switch to OFF position. Disconnect fuel level sensor unit and fuel pump harness connector. Using an ohmmeter, measure resistance between fuel level sensor unit and fuel pump terminals No. 1 and 3. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Resistance should be one ohm at 77°F (25°C). If resistance is as specified, go to next step. If resistance is not as specified, replace fuel pump.
- No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.