For 1990-2009 cars only
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 P1A8F: 14 Volt Power Module Current Sensor OvercurrentCircuit/System Description
The starter/generator control module (SGCM) monitors the 14-volt power module current sensor for an overcurrent condition to protect the MOSFET. In the hardware an overcurrent protection circuit is used to limit the current, and software monitors for an overcurrent reading in the sensor.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
The 12 volt charge is greater than 150 amps or less than -150 amps for 2 seconds
Action Taken When the DTC Sets
| • | In the software fault: |
| - | Stop PWM (MGU shutdown) |
| - | APM PWM off |
| • | In the hardware fault: |
| - | Stop PWM (MGU shutdown) |
| - | APM PWM off |
| - | Battery disconnection (disconnect SW on/off) |
Hybrid system is disabled.
Conditions for Clearing the DTC
| • | In the software fault, APM current less than +/- 10 amps |
| • | 12VOUT is greater than 7 volts. |
| • | APMTEMP is less than 105°C (221°F) for 160 ms. |
| • | Clears 30 seconds after cycle wake up signal. |
Diagnostic Aids
| • | Battery cable short to ground |
| • | Fuse/relay box electrical failures |
| • | FET breakdown |
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
- Inspect for any open fuses.
- Inspect all the 12-volt battery connections for short to ground as follows:
- With a scan tool, clear the DTC.
- Ignition OFF, wait 30 seconds.
- Ignition ON, operate the vehicle within the Conditions for Running the DTC and verify the DTC does not reset.
| • | At battery |
| • | At SGCM |
| • | At fuse block |
| ⇒ | 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
