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P0ACB




DTC P0A9C-P0A9E, P0AC6-P0AC8, P0ACB-P0ACD, P0AE9, P0AEA, or P0AEB

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (with HP2) (Initial Inspection and Diagnostic Overview)Diagnostic System Check - Vehicle (without HP2) (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptors
DTC P0A9C
- Hybrid Battery 1 Temperature Sensor Performance

DTC P0A9D
- Hybrid Battery 1 Temperature Sensor Circuit Low Voltage

DTC P0A9E
- Hybrid Battery 1 Temperature Sensor Circuit High Voltage

DTC P0AC6
- Hybrid Battery 2 Temperature Sensor Performance

DTC P0AC7
- Hybrid Battery 2 Temperature Sensor Circuit Low Voltage

DTC P0AC8
- Hybrid Battery 2 Temperature Sensor Circuit High Voltage

DTC P0ACB
- Hybrid Battery 3 Temperature Sensor Performance

DTC P0ACC
- Hybrid Battery 3 Temperature Sensor Circuit Low Voltage

DTC P0ACD
- Hybrid Battery 3 Temperature Sensor Circuit High Voltage

DTC P0AE9
- Hybrid Battery 4 Temperature Sensor Performance

DTC P0AEA
- Hybrid Battery 4 Temperature Sensor Circuit Low Voltage

DTC P0AEB
- Hybrid Battery 4 Temperature Sensor Circuit High Voltage

Diagnostic Fault Information





Typical Scan Tool Data









Circuit/System Description

The drive motor generator battery has four hybrid battery temperature sensors. The hybrid battery temperature sensors are located on the top of the hybrid batteries. The temperature sensor is a variable resistor that measures the temperature of the hybrid batteries. The control module supplies 5 V to the signal circuit and a ground for the low reference circuit. The hybrid battery temperature sensor resistance changes with battery 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 battery temperature sensors to determine the hybrid battery temperature to control the battery cooling fan operation.

Conditions for Running the DTC

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

Conditions for Setting the DTC

P0A9C, P0AC6, P0ACB, and P0AE9

The hybrid battery temperature sensor is in normal operating range, but is 15°C (27°F) different from the other 3 sensors.

P0A9D, P0AC7, P0ACC, and P0AEA

The hybrid battery temperature is greater than 95°C (203°F) and one other temperature sensor is less than 70°C (158°F).

P0A9E, P0AC8, P0ACD, and P0AEB

The hybrid battery temperature is less than -40°C (-40°F).

Action Taken When the DTC Sets

* If two sensors fail, the drive motor generator battery sends a message to the HPCM to reduce the power use limit to 50 percent and the battery vent fan will default to run.
* If all four sensors fail, the state of charge (SOC) will be considered invalid.

Conditions for Clearing the DTC

DTCs P0A9C, P0A9D, P0A9E, P0AC6, P0AC7, P0AC8, P0ACB, P0ACC, P0ACD, P0AE9, P0AEB, and P0AEA are type B DTCs.

Reference Information
Schematic Reference

Hybrid Energy Storage Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Drive Motor Generator Battery Cooling Description (Drive Motor Generator Battery Cooling Description)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information
Special Tools

EL-48900 HEV Safety Kit

Circuit/System Verification

1. Ignition ON, command the battery cooling fan ON and OFF with a scan tool. Listen for the operation of the fan.
2. Ignition ON, observe all four hybrid battery module temperature sensor parameters with a scan tool. The readings should be between -39 and +95°C (-38 and +203°F) with no greater than a 15°C (27°F) difference between any of the four temperature sensor readings.

Circuit/System Testing

1. Verify that DTCs P0A80, P0A81 and P0BBD are not set.

• If any of the specified DTCs are set, repair them first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code Descriptions).

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.


2. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling (High Voltage Disabling).
3. Remove the drive motor generator battery cover. Refer to Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement (Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement).
4. Inspect the battery for the following conditions:

* 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.

5. Ignition OFF, disconnect the X3 connector at the GBCM.
6. Ignition OFF, test for less than 5 Ohms between the low reference terminals of the GBCM listed below and ground.

* Terminal 2
* Terminal 4
* Terminal 6
* Terminal 8

• If greater than the specified range, test the GBCM ground circuits for an open/high resistance. If the circuits test normal, replace the GBCM.

7. Ignition ON, verify the scan tool Hybrid Batt. Mod. 1-4 Temperature parameters are -40°C (-40°F).

• If greater than the specified value, replace the GBCM.

8. Install a 3 A fused jumper wire between the appropriate signal terminal listed below and the low reference terminal 2 of the GBCM. Verify the appropriate scan tool Hybrid Batt. Mod. 1-4 Temperature is 100°C (212°F).

* Terminal 1, for temperature sensor 1
* Terminal 3, for temperature sensor 2
* Terminal 5, for temperature sensor 3
* Terminal 7, for temperature sensor 4

• If less than the specified value, replace the GBCM.

9. 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 (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 (Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement).
3. Allow the batteries to cool.
4. Unclip and remove all four hybrid battery temperature sensors from the batteries and allow them to stand at room air temperature for approximately 3 minutes.
5. Ignition OFF, disconnect the X3 connector at the GBCM.
6. Test the resistance across each temperature sensor 5 V reference and low reference circuits. Refer to Temperature Versus Resistance (Temperature Versus Resistance). All sensors should measure within 500 Ohms of each other.

• If greater than 500 Ohms , replace the drive motor battery sensor module wiring harness assembly.

7. If all circuits test normal, replace the drive motor generator battery control module.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.

* Generator Battery Vent Fan Replacement (Generator Battery Vent Fan Replacement)
* Drive Motor Battery Sensor Module Wiring Harness Replacement (Drive Motor Battery Sensor Module Wiring Harness Replacement)
* Control Module References (Programming and Relearning) - for drive motor generator battery control module replacement, setup and programming.

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