GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The following DTC is for the batteries located in the generator battery carrier:

Battery voltage sensors allow the generator battery control module to monitor the voltage of the batteries in the generator battery carrier. The generator battery control module monitors the voltage drop across the battery voltage sensors and uses the inputs for hybrid calculations.

P0A7F is for the hybrid battery pack life.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0A7F Hybrid Battery Pack Life

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The Battery Pack does not have enough power and/or energy to support IEO (Idle Engine OFF) and Auto Start events. This occurs when the SOC reaches a set calibration.

Conditions for Clearing the DTC

    • The DTC will become history if the generator battery control module no longer detects a fault.
    • The history DTC will clear after 100 fault-free ignition cycles.
    • The DTC can be cleared with a scan tool.

Step

Action

Yes

No

Schematic Reference: Hybrid Energy Storage Schematics

Connector End View Reference: Hybrid Energy Storage Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Test each battery for low charge or over charge. Refer to Battery Inspection/Test .

Do the batteries test good?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Replace the appropriate battery. Refer to Generator Battery Replacement .

Did you complete the replacement?

Go to Step 4

--

4

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK