P0A8F

DTC P0A8F

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptor
DTC P0A8F
- 14 Volt Power Module System Performance

Circuit/System Description

When set with no accompanying DTCs, this diagnostic is an internal fault detection of the Accessory Power Module (APM) assembly. This fault is handled inside the APM assembly and no external circuits are involved.

Conditions for Running the DTC

* Ignition voltage is 7-16V.
* The APM runs a portion of the diagnostics for this DTC at Accessory/Ignition On.
* The APM runs more diagnostics for DTC P0A8F at APM 14V enable active.

Conditions for Setting the DTC

* An associated DTC has caused an internal APM malfunction or
* The APM has detected an internal malfunction.

Action Taken When the DTC Sets

* DTC P0A8E is a Type C DTC.
* The engine control module (ECM) will command the charge indicator and or warning message to be illuminated on the instrument panel cluster (IPC) and the driver information center (DIC), if equipped.
* The ECM will not illuminate the malfunction indicator lamp (MIL).
* The Hybrid Powertrain Control Module (HPCM) stores the DTC information in memory when the diagnostic runs and fails.
* The APM will shutdown 14V conversions based on the associated DTC.

Conditions for Clearing the DTC

* DTC P0A8E is a Type C DTC.
* Ignition off, APM goes to sleep.

Reference Information
Schematic Reference

Hybrid Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Drive Motor Generator Control Module Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Start the Engine.
2. Check for any other DTCs.

• If other APM associated DTCs are set, diagnose those DTCs first.

3. Retest for DTC P0A8F.

Circuit/System Testing

Reprogram the APM and recheck for DTCs.

If the DTC resets with no accompanying DTCs, replace the APM.

Component Testing

1. Turn the Ignition to ON.
2. Connect a DMM to the 12V battery.
3. Use the Device Control "APM set point control" to turn on the APM 14V system.
4. Vary the voltage setpoint with the scan tool insuring that the DMM tracks the commanded voltage.

• If the APM set point control fails, replace the APM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for APM replacement, setup, and programming.