DTC P1220 - Fuel Pump Control Module (FPCM)
- Check Power Supply
Turn ignition off. Disconnect FPCM, located in left side of luggage compartment. Disconnect fuel pump harness connector, located behind inspection cover under rear seat. Using a voltmeter, measure voltage between FPCM connector terminal No. 3 (Black/Yellow wire) and ground. Also, measure voltage between fuel pump connector terminal No. 1 (Black/Yellow wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 32 or fault in Black/Yellow wire. - Check Ground Circuit
Leave ignition off. Disconnect dropping resistor harness connectors. Check continuity between dropping resistor connector terminal No. 2 (Black wire) and ground. Also, check continuity between FPCM harness connector terminal No. 2 (Black wire) and ground. If no continuity exists, repair open in Black wire. If continuity exists, go to next step. - Check continuity as follows:
- Between dropping resistor harness connector terminal No. 1 (Green/Red wire) and fuel pump harness connector terminal No. 2 (Green/Red wire).
- Between dropping resistor harness connector terminal No. 1 and FPCM connector terminal No. 1 (Green/Red wire).
- Between fuel pump harness connector terminal No. 2 (Green/Red wire) and FPCM connector terminal No. 1 (Green/Red wire).
If continuity exists, go to next step. If continuity does not exists, repair fault in Green/Red wire.
- Check Output Signal Circuit
Turn ignition off. Disconnect ECM harness connector. Using an ohmmeter, check continuity between ECM harness connector terminal No. 15 and FPCM harness connector terminal No. 4 (Black/Pink wire). If no continuity exists, repair open in Black/Pink wire. If continuity exists, go to next step. - Check Input Signal Circuit
Using an ohmmeter, check continuity between ECM harness connector terminal No. 28 and FPCM harness connector terminal No. 1 (Green/Red wire). Also, check continuity between ECM harness connector terminal No. 28 (Green/Red wire) and ground. If continuity exists, repair short to ground in Green/Red wire. If continuity does not exist, go to next step. - Check Dropping Resistor
Disconnect dropping resistor harness connector. Measure resistance between connector terminals. See Fig 1. If resistance is about 0.9 ohms at 77°F (25°C), go to next step. If resistance is not about 0.9 ohms at 77°F (25°C), replace dropping resistor. - Check FPCM
Start engine and warm to operating temperature. Turn ignition off and wait at least 5 seconds. Start engine and allow to idle. Measure voltage between FPCM connector terminals 1 and 2. See Fig 2. Voltage should zero volts within 30 seconds of starting engine and about 3.7 volts after 30 seconds of starting engine. If voltage is not as specified, replace FPCM. If voltage is as specified, disconnect and reconnect harness connectors in circuit and retest system.