Pinpoint Test G : U012D, U042E: Notes
WARNING: This page is about a different car, the 2018 Ford Focus. However, it is still accessible from the selected car via links, so may be relevant.
Refer to Charging System for schematic and connector information.
Normal Operation and Fault Conditions
The charging system supplies voltage to the battery and the vehicle electrical system through the battery B+ cable. The PCM communicates the desired voltage setpoint to the generator internal voltage regulator over a LIN communication circuit. The generator communicates the generator load and error conditions to the PCM over this LIN.
Diagnostic Trouble Code (DTC) Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| U012D | Lost Communication With Generator Control Module | This DTC sets if the PCM does not detect communication through the LIN circuit. This can be a result of an open or short in the LIN circuit. This DTC also sets if the generator B+ circuit is open. |
| U042E | Invalid Data Received From Generator Control Module | This DTC sets when the PCM receives invalid data from the generator. |
Possible Sources
- Battery monitoring sensor
- Generator
- Wiring, terminals or connectors
Visual Inspection and Diagnostic Pre-checks
- Inspect high current BJB fuse 2 (150A).
- Inspect high current BJB for loose or corroded connections.