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