Pinpoint Test E : DTC U012D, U042E: Notes
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 monitors the generator output through a dedicated LIN communication circuit. The PCM uses this LIN circuit to communicate the desired voltage setpoint to the generator internal voltage regulator. The generator also uses this to communicate the generator load and error conditions to the PCM.
Diagnostic Trouble Code (DTC) Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| U012D | Lost Communication With Generator Control Module | 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 | Sets when the PCM receives invalid data from the generator. |
Possible Sources
- BCM
- Generator
- PCM
- Wiring, terminals or connectors
Visual Inspection and Diagnostic Pre-checks
- Inspect grounds G100, G101, G102 and G104 for loose or corroded connections.
- Inspect high current BJB for loose or corroded connections.
- Inspect the FEAD belt.
- Inspect the battery monitoring sensor.
- Inspect the BJB fuse 22 (15A).