Diagnostic Instructions
DTC Descriptor
DTC P0A7C: Starter/Generator Control Module Motor Electronics Overtemperature
Circuit/System Description
The starter/generator control module (SGCM) temperature sensor is used for system overheat protection. The SGCM monitors the board temperature sensor for an overtermperature condition.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
Board temperature is greater than 120°C (248°F) for 1 second.
Action Taken When the DTC Sets
• | Stop PWM (MGU shutdown) |
Conditions for Clearing the DTC
Board temperature is less than 120°C (248°F) for 3 second.
Diagnostic Aids
Possible engine or SGCM cooling system failure due to the following:
• | Restricted radiator air flow. |
• | Restricted engine coolant flow. |
• | Faulty engine water pump. |
• | Inoperative SGCM coolant pump. |
Reference Information
Schematic Reference
Hybrid Controls Schematics
Connector End View Reference
Hybrid Controls Connector End Views
Electrical Information Reference
Scan Tool Reference
Scan Tool Data List
Circuit/System Verification
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.
- Using the scan tool verify the SGCM coolant pump operates
- If DTC is history, refer to
Testing for Intermittent Conditions and Poor Connections
.
- With ignition ON, observe the scan tool SGCM temperature sensor parameters.
⇒ | If only the SGCM board temperature sensor reads high, replace the SGCM. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
Control Module References
for SGCM replacement, setup, and programming