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DTC P1105: Upper Generator Fault Detected

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  1. Turn ignition switch to LOCK position. Disconnect upper generator 3-pin harness connector. Disconnect generator 4-pin in-line harness connector C1019. In-line harness connector C1019 is located in left rear corner of engine compartment, above brake master cylinder. See Fig 1. 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.
  2. Measure voltage between ground and upper generator terminal B+ (Black/Orange wire). If battery voltage is present, go to next step. If battery voltage is not present, repair circuit or fusible links between battery and upper generator. See WIRING DIAGRAMS .
  3. Measure voltage between ground and upper generator harness connector terminal "A" (Orange/Light Blue wire). See Fig 2. If voltage is 10 volts or more, go to next step. If voltage is less than 10 volts, repair open in circuit or fusible links between battery and upper generator. See WIRING DIAGRAMS .
  4. Turn ignition switch to RUN position. Measure voltage between ground and upper generator harness connector terminal "I" (White/Yellow wire). If voltage is less than 10 volts, go to next step. If voltage is 10 volts or more, go to step  6.
  5. Turn ignition switch to LOCK position. Disconnect PCM 104-pin harness connector. Measure resistance in White/Yellow wire between upper generator harness connector terminal "I" and PCM harness connector terminal No. 35. See Fig 2 and Fig 3 . If resistance is less than 5 ohms, go to step  8. If resistance is 5 ohms or greater, repair open in White/Yellow wire between upper generator and PCM. See WIRING DIAGRAMS .
  6. Connect upper generator harness connector. Connect PCM harness connector. Disconnect lower generator 3-pin harness 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 UPPER GENERATOR  under REMOVAL & INSTALLATION.
  7. 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. See UPPER GENERATOR  under REMOVAL & INSTALLATION. If generator tests okay, system is operating properly at this time.
  8. Inspect PCM harness connector for corrosion and pushed out pins. Connect PCM harness connector, ensuring it is connected properly. Connect all disconnected connectors. Operate system. If fault is still present, replace PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. If fault is not present, system is operating properly at this time.
Fig 1: Identifying In-Line Harness Connector C1019 Terminals
G00188460Courtesy of FORD MOTOR CO.
Fig 2: Identifying Generator 3-Pin Connector Terminals
G00264286Courtesy of FORD MOTOR CO.
Fig 3: Identifying Powertrain Control Module Harness Connector Terminals
G96F31315Courtesy of FORD MOTOR CO.
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