For 1990-2009 cars only
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P1AB1: Starter/Generator Phase U-V-W Current Sensor OvercurrentCircuit/System Description
The starter/generator control module (SGCM) monitors the phase U/V/W current sensor to detect 3 phase overcurrent and to protect the MOSFET.
Conditions for Running the DTC
| • | Engine is running. |
| • | Wake up signal is ON. |
Conditions for Setting the DTC
Over current signal set for 20 ms.
Action Taken When the DTC Sets
| • | Stop PWM (MGU shutdown) |
| • | APM PWM OFF |
| • | Battery disconnection (disconnect SW on/off) |
Conditions for Clearing the DTC
Over current signal not valid
Diagnostic Aids
| • | Possible MGU winding short to other winding or short to case |
| • | Possible FET breakdown or gate driver circuit fault |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Starter/Generator Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Disconnect the 3-phase cables from the SGCM. Refer to Generator Control Module 3-Phase Cable Assembly Replacement.
- Test each of the 3-phase cables individually for a short to ground.
- Test each of the 3-phase cables individually for a short to ground.
- If all circuits test normal, replace the SGCM.
| ⇒ | If any circuit indicates a short to ground , disconnect the 3-phase cables from the MGU. |
| ⇒ | If the short to ground condition is longer present, replace the MGU. |
| ⇒ | If any circuit does not test normal, replace the 3-phase cable assembly. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for SGCM replacement, setup, and programming |
