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 P1A97: Starter/Generator Control Module Hybrid Battery Voltage Sense Circuit Low VoltageDTC P1A98: Starter/Generator Control Module Hybrid Battery Voltage Sense Circuit High Voltage
Circuit/System Description
The starter/generator control module (SGCM) monitors the hybrid battery system voltage for a low and high condition to detect the failure of the 36-volt output voltage sensor that is below or above a valid range.
Conditions for Running the DTC
P1A97, P1A98
The engine is running.
Conditions for Setting the DTC
P1A97
| • | Sensor signal is less than 0.2 volt for continuous 20 ms. |
| • | Sensor signal is less than 0.2 volt for 20 ms and 36-volt battery voltage is greater than 5 volts for 20 ms. |
P1A98
Sensor output voltage less than 4 volts and 36-volt battery voltage is greater than 5 volts for 20 ms.
Action Taken When the DTC Sets
P1A97, P1A98
| • | Stop PWM (MGU shutdown). |
| • | APM PWM off. |
Conditions for Clearing the DTC
P1A97, P1A98
Closes 30 seconds after cycle wake up signal.
Diagnostic Aids
P1A97
Possible internal sensor shorted.
P1A98
Possible internal sensor open.
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 Verification
Caution: To help avoid personal injury, be careful when working in the vicinity of the generator battery disconnect control module. Internal components will still be live, 36V potential, even when the cover has been opened or removed.
- With a scan tool, clear the DTC.
- Ignition OFF, wait 30 seconds.
- Ignition ON, operate the vehicle within the Conditions for Running the DTC.
| ⇒ | If the DTC resets, replace the SGCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for SGCM replacement, setup, and programming
