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 Descriptors
DTC P1A7C: Starter/Generator Control Module Temperature Sensor Circuit Low VoltageDTC P1A7D: Starter/Generator Control Module Temperature Sensor Circuit High Voltage
Circuit/System Description
The starter/generator control module (SGCM) monitors the temperature sensor circuit to detect shorted low or high failure.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
P1A7C
Sensor output voltage less than 0.2 volt for 1 second
P1A7D
Sensor output voltage greater than 4.6 volts for 1 second
Action Taken When the DTC Sets
P1A7C, P1A7D
| • | 50 percent maximum torque limit |
| • | APM 50 percent maximum current output |
Conditions for Clearing the DTC
P1A7C, P1A7D
Return to normal range for 10 seconds
Diagnostic Aids
P1A7C
Possible sensor short to ground or open
P1A7D
Possible short to voltage or open
Reference Information
Schematic Reference
Connector End View Reference
Hybrid Controls Connector End Views
Electrical Information Reference
Scan Tool Reference
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.
P1A7C, P1A7D
- If DTC is history, refer to Testing for Intermittent Conditions and Poor Connections .
- If DTC is current, replace the SGCM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for SGCM replacement, setup, and programming
