Diagnostic Instructions
DTC Descriptor
DTC P1A70: Starter/Generator Control Module System Voltage Performance
Circuit/System Description
The starter/generator control module (SGCM) monitors the performance to detect 12-volt DC wire electrical failure by comparing the 12-volt input to the 12-volt output values. If the difference is greater than 5 volts, the DTC sets.
Conditions for Running the DTC
• | The engine is running. |
• | Hybrid mode is active. |
Conditions for Setting the DTC
The 12-volt power supply - 12-volt output voltage is greater than 5 volts for 119 ms and any fault during 15 seconds wait period.
Action Taken When the DTC Sets
• | Stop PWM (MGU shutdown). |
Conditions for Clearing the DTC
Cycle wake up signal.
Diagnostic Aids
Possible 12-volt battery or APM voltage sensor stuck.
Reference Information
Schematic Reference
Hybrid Controls Schematics
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.
- 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