DTC P1105: Upper Generator Fault Detected
WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
- Check Upper Generator Connections
Turn ignition switch to LOCK position. Disconnect upper generator connectors. Inspect connectors for damage or loose connections. If connectors are okay, restore connections and go to next step. If connectors are not okay, repair as necessary. - Check The Upper Generator B+ Voltage
Measure voltage between ground and upper generator terminal B+ (Yellow/White or Red wire). If battery voltage is present, go to next step. If battery voltage is not present, repair circuit or fusible links between batteries and upper generator. See WIRING DIAGRAMS . Clear DTCs. Test system for normal operation. - Check The Upper Generator "A" Circuit
Disconnect upper generator 3-pin connector. Measure voltage between ground and upper generator connector terminal No. 3 (Orange/Light Blue wire). See Fig 1. If voltage is 12 volts or more, go to next step. If voltage is less than 12 volts, repair open in circuit or fusible links between batteries and upper generator. See WIRING DIAGRAMS . Clear DTCs. Test system for normal operation. - Check Upper Generator "I" Circuit Voltage
Turn ignition switch to RUN position. Measure voltage between ground and upper generator connector terminal No. 1 (Light Green/Red wire). See Fig 1. If voltage is less than 10 volts, go to next step. If voltage is 10 volts or more, go to step 6. - Check The Upper Generator "I" Circuit For An Open Or Short To Ground
Turn ignition switch to LOCK position. Disconnect PCM connector C175 or connector C1381c. PCM is located at left rear of engine compartment. Measure resistance between upper generator harness connector terminal No. 1 (Light Green/Red wire) and 7.3L PCM connector C175 terminal No. 35 or 6.0L PCM connector C1381c terminal No. 1, and between generator connector terminal No. 1 (Light Green/Red wire) and ground. See Fig 2 or Fig 3 . If resistance is less than 5 ohms between generator and PCM, and greater than 10 k/ohms between generator and ground, go to step 8. If resistance is not less than 5 ohms between generator and PCM, or greater than 10 k/ohms between generator and ground, repair Light Green/Red wire between upper generator and PCM or ground. See WIRING DIAGRAMS . Clear DTCs. Test system for normal operation. - Check The Upper Generator Voltage
Connect upper generator connector. Connect PCM harness connector. Disconnect lower generator 3-pin connector. Start engine and let idle. Wait 2 minutes (until glow plugs turn off). Measure voltage between primary battery terminals. If voltage is 13 volts or more, go to next step. If voltage is less than 13 volts, replace upper generator. See GENERATOR (UPPER) under REMOVAL & INSTALLATION. - Check The Upper Generator Output
Perform load and no-load tests on upper generator. See GENERATOR LOAD TEST and GENERATOR NO-LOAD TEST under ON-VEHICLE TESTING. If generator does not test okay, replace upper generator. If generator tests okay, system is operating properly at this time. - Check For Correct PCM Operation
Inspect PCM connector for corrosion and pushed out pins. Connect PCM connector, ensuring it is connected properly. Connect all disconnected connectors. Operate system. If fault is still present, replace PCM. If fault is not present, system is operating properly at this time.