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 Descriptors

DTC P0AAD: Hybrid Battery Pack Air Temperature Sensor 1 Performance

DTC P0AAE: Hybrid Battery Pack Air Temperature Sensor 1 Circuit Low Voltage

DTC P0AAF: Hybrid Battery Pack Air Temperature Sensor 1 Circuit High Voltage

DTC P0AB2: Hybrid Battery Pack Air Temperature Sensor 2 Performance

DTC P0AB3: Hybrid Battery Pack Air Temperature Sensor 2 Circuit Low Voltage

DTC P0AB4: Hybrid Battery Pack Air Temperature Sensor 2 Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Air Inlet Temperature Sensor Signal

P0AAE

P0AAF

P0AAF

--

Air Inlet Temperature Sensor Low Reference

--

P0AAF

--

--

Air Outlet Temperature Sensor Signal

P0AB3

P0AB4

P0AB4

--

Air Outlet Temperature Sensor Low Reference

--

P0AB4

--

--

Typical Scan Tool Data

Hybrid Batt. Inlet Air Temperature

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Range: 26°C (79°F)

Air Inlet Temperature Sensor Signal

100°C (212°F)

-40°C (-40°F)

-40°C (-40°F)

Air Inlet Temperature Sensor Low Reference

--

-40°C (-40°F)

--


Hybrid Batt. Inlet Air Temperature Sensor

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Range: 0.5 to 4.3 Volts

Air Inlet Temperature Sensor Signal

0 Volts

4.75 Volts

5 Volts

Air Inlet Temperature Sensor Low Reference

--

4.75 Volts

--


Hybrid Batt. Outlet Air Temperature

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Range: 26°C (79°F)

Air Outlet Temperature Sensor Signal

100°C (212°F)

-40°C (-40°F)

-40°C (-40°F)

Air Outlet Temperature Sensor Low Reference

--

-40°C (-40°F)

--


Hybrid Batt. Outlet Air Temp Sensor

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Range: 0.5 to 4.3 Volts

Air Outlet Temperature Sensor Signal

0 Volts

4.75 Volts

5 Volts

Air Outlet Temperature Sensor Low Reference

--

4.75 Volts

--

Circuit/System Description

The drive motor generator battery assembly has an air inlet and air outlet temperature sensors. The air inlet and air outlet temperature sensors are located on the inlet and outlet air ducts of the hybrid battery vent fan. The air inlet temperature sensor is referred to as sensor 1 and the air outlet temperature sensor is referred to as sensor 2. The air temperature sensors are a variable resistor that measures the temperature of the inlet and outlet air. The control module supplies 5 V to the signal circuit and a ground for the low reference circuit. The air inlet and outlet temperature sensor resistance changes with temperature. The lower the temperature, the higher the resistance of the sensor. The higher the temperature, the lower the resistance of the sensor. The drive motor generator battery control module (GBCM) uses the air inlet and outlet temperature sensors to determine if air is circulating through the drive motor generator battery assembly.

Conditions for Running the DTC

    • The ignition is ON.
    • The 12 V battery voltage is 9-18 V.

Conditions for Setting the DTC

P0AAF and P0AB4

The hybrid battery pack air temperature sensor 1 or 2 is less than -40°C (-40°F).

P0AAE and P0AB3

The hybrid battery pack air temperature sensor 1 or 2 is greater than 95°C (203°F).

P0AAD

The hybrid battery cooling fan is ON and the difference between sensor 1 and 2 is greater than 10°C (18°F) difference for 9 seconds.

P0AB2

The hybrid battery cooling fan is ON and the outlet air temperature is greater than maximum hybrid battery temperature value by 10°C (18°F) for 9 seconds.

Action Taken When the DTC Sets

    • The drive motor generator battery sends a message to the HPCM to reduce the power by 50 percent.
    • DTCs P0AAD, P0AAE, P0AAF, P0AB2, P0AB3, and P0AB4 are type B DTCs.

Conditions for Clearing the DTC

DTCs P0AAD, P0AAE, P0AAF, P0AB2, P0AB3, and P0AB4 are type B DTCs.

Reference Information

Schematic Reference

Hybrid Cooling Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Drive Motor Generator Battery Cooling Description

Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-48900 HEV Safety Kit

Circuit/System Verification

  1. Ignition ON, observe the hybrid battery air inlet and outlet temperature parameters with a scan tool. The hybrid battery inlet and outlet air temperature should be between -39 and +95°C (-38 and +203°F).
  2. Ignition ON, using a scan tool, command the hybrid battery pack fan speed to 60 percent and let it run for 2 minutes. The inlet and outlet air temperature parameters should be within 10°C (18°F) of each other.

Circuit/System Testing

  1. Inspect the inlet air vents for any obstructions or blockages that are external to the drive motor generator battery.
  2. If inlet air obstructions or blockages are found, remove or repair as needed.

    Danger: Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:

       • Safety glasses with appropriate side shields when within 50 feet of the vehicle, either indoors or outdoors
       • Certified and up-to-date Class "0" Insulation gloves rated at 1000V with leather protectors
          -  Visually and functionally inspect the gloves before use.
          -  Wear the Insulation gloves at all times when working with the high voltage battery assembly, whether the system is energized or not.
    Failure to follow the procedure exactly as written may result in serious injury or death.

  3. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling.
  4. Remove the drive motor generator battery cover. Refer to Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement.
  5. Inspect the battery for the following conditions:
  6. • Obstructed inlet or outlet duct
    • Damaged fan blades
    • Missing or damaged internal foam seals
    If any of the conditions are present, repair or replace any damaged components.
  7. Ignition OFF, disconnect the X3 connector at the GBCM.
  8. Ignition OFF, test for less than 5 Ω between the low reference terminals of the GBCM listed below and ground.
  9. • Terminal 10
    • Terminal 12
    If greater than the specified range, test the GBCM ground circuits for an open/high resistance. If the circuits test normal, replace the GBCM.
  10. Ignition ON, verify the scan tool Hybrid Batt. Inlet Air Temperature and Hybrid Batt. Outlet Air Temperature parameters are -40°C (-40°F).
  11. If greater than the specified value, replace the GBCM.
  12. Install a 3 A fused jumper wire between the signal terminal 9 and the low reference terminal 10 of the GBCM. Verify the scan tool Hybrid Batt. Inlet Air Temperature is 100°C (212°F).
  13. If less than the specified value, replace the GBCM.
  14. Install a 3 A fused jumper wire between the signal terminal 11 and the low reference terminal 12 of the GBCM. Verify the scan tool Hybrid Batt. Outlet Air Temperature is 100°C (212°F).
  15. If less than the specified value, replace the GBCM.
  16. If all circuits test normal, test or replace the temperature sensors.

Component Testing

Temperature Sensor Test

    Danger: Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:

       • Safety glasses with appropriate side shields when within 50 feet of the vehicle, either indoors or outdoors
       • Certified and up-to-date Class "0" Insulation gloves rated at 1000V with leather protectors
          -  Visually and functionally inspect the gloves before use.
          -  Wear the Insulation gloves at all times when working with the high voltage battery assembly, whether the system is energized or not.
    Failure to follow the procedure exactly as written may result in serious injury or death.

  1. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling.
  2. Remove the drive motor generator battery cover. Refer to Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement.
  3. Remove hybrid battery air inlet and outlet temperature sensors and allow them to stand at room air temperature for approximately 3 minutes.
  4. Ignition OFF, disconnect the X3 connector at the GBCM.
  5. Verify the resistance between each temperature sensor signal and low reference circuits is within the range specified in Temperature Versus Resistance, and within 500 Ω of each other.
  6. If not within the specified range, replace the drive motor battery sensor module wiring harness. Refer to Generator Battery Temperature Sensor Location for the proper locations.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

    •  Drive Motor Battery Sensor Module Wiring Harness Replacement
    •  Control Module References - for drive motor generator battery control module replacement, setup and programming.