GM Service Manual Online
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 P0A80: Replace Hybrid Battery Pack

Circuit/System Description

The battery energy control module (BECM) monitors the battery pack resistance to verify that it is not above the system resistance criteria (55 m ohms) where it will affect the hybrid vehicle performance.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

Pack resistance is greater than resistance criteria. Where resistance criteria = TempFactorLookup + SOCFactorLookup;

Where TempFactorLookup(T) =

Temperature Celsius/Fahrenheit

Resistance in mOhms

-40/-40

0.18

-30/-22

0.18

-20/-4

0.18

-10/14

0.18

0/32

0.18

10/50

0.18

20/68

0.055

30/86

0.055

40/104

0.055

50/122

0.055

60/140

0.055

70/158

0.055

80/176

0.055

90/194

0.055

100/212

0.055

110/230

0.055

120/248

0.055

Where SOCFactorLookup(T) =

State of Charge (SOC)

Resistance in mOhms

0

0.007

10

0.007

20

0.004

30

0.003

40

0.001

50

0

60

0

70

0

80

0.015

90

0.003

100

0.003

Action Taken When the DTC Sets

Does not affect hybrid system operation.

Conditions for Clearing the DTC

The following conditions must be present:

    • Battery voltage = Valid
    • Battery current = Valid
    • Battery temperature = Valid
    • Battery state of charge = Valid
    • Battery resistance low = Valid
    • Battery resistance severe low = Valid
    • Battery resistance calc. regression = Valid
    • All current sensor faults = Not Fail
    • All voltage sensor faults = Not Fail
    • Battery temperature not less than -7°C (19.4°F)
    • Battery state of charge not greater than 90 percent

Reference Information

Schematic Reference

Hybrid Energy Storage Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Generator Battery Carrier Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. If the other DCTs are set, they should be diagnosed first.
  2. Review the vehicle service history to determine if the battery pack has been replaced previously and not been reset with scan tool.
  3. Install the scan tool. Observe the Calc Hybrid Batt Resistance parameter in the ECM/Hybrid data list.
  4. If resistance is greater than 55 m ohms, continue with Circuit/System Testing.
    If resistance is less than 50 m ohms, clear the DTC and road test vehicle to determine if the DTC resets.

Circuit/System Testing

  1. Gain access to the hybrid battery pack connections. Refer to Hybrid Battery Service Disconnect/Connect.
  2. Verify the hybrid battery pack connections are within specifications. Refer to Fastener Tightening Specifications
  3. If connections are within specifications, replace the battery pack.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Generator Battery Replacement