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
Hybrid Controls Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
Caution: To help avoid personal injury, additional precautions must be taken prior to working on the generator control module or the generator starter. After removing the 36V battery cables from the generator battery, remove both engine wiring harness connectors from the generator control module. Wait at least 5 minutes and then remove the generator control module cover. Verify voltage levels at all 36V, 12V, and 3-phase connections, are less than 3 volts using a DMM before proceeding.
- 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 |
