P0AFB

DTC P0AFB

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructionsprovides an overview of each diagnostic category.

DTC Descriptor
DTC P0AFB
- Hybrid Battery System Voltage High - ACCM 300V

Diagnostic Fault Information






Typical Scan Tool Data










Circuit/System Description

The air conditioner control module (ACCM) monitors the high voltage direct current (HVDC) voltage to ensure that the voltage stays within the proper range. Damage to components, and incorrect data may occur when the voltage is out of range. If the ACCM detects high HVDC voltage, then DTC P0AFB will set.

Conditions for Running the DTC

* The engine is running or is in autostop mode.
* The 12 V system voltage is between 9.5-18 V.

Conditions for Setting the DTC

The ACCM detects that the hybrid battery voltage is greater than 415 V for 3 seconds.

Action Taken When the DTC Sets

The air conditioning is disabled.

Conditions for Clearing the DTC

* The DTC will pass when the ACCM detects a hybrid battery voltage less than 405 V for 3 seconds.
* A history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

Diagnostic Aids

A high voltage DTC in multiple modules indicates a concern in the charging system.

Reference Information
Schematic Reference

* HVAC Schematics HVAC - Automatic
* Hybrid Controls Schematics

Connector End View Reference

Component Connector End Views Connector End Views By Name
Description and Operation

* Heating and Air Conditioning System Description and Operation Heating and Air Conditioning System
* High Voltage Monitoring Systems Description

Electrical Information Reference

* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Programming and Relearningfor scan tool information

Circuit/System Verification

1. Verify that no hybrid powertrain control module (HPCM) DTCs are set due to high battery voltage.

• If the specified DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

2. Engine running or autostop, observe the scan tool ACCM High Battery Voltage parameter. The reading should be between 225 V and 380 V.

• If greater than the specified range, replace the ACCM.

Repair Instructions

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

Control Module References Programming and Relearningfor ACCM replacement, setup, and programming.