P0AC6
DTC P0A9C-P0A9E, P0AC6-P0AC8, P0ACB-P0ACD, P0AE9, P0AEA, or P0AEB
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (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 control module will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the drive motor generator battery control module to the drive motor generator control module through the serial data circuit. The drive motor generator control module is the host controller for diagnostic trouble code (DTC) information.
The drive motor generator battery control module has four drive motor battery temperature sensor inputs. The temperature sensors are located inside the drive motor generator battery assembly, The temperature sensor is a 2-wire 10 k ohm variable thermistor that measures the temperature of the drive motor generator batteries. The drive motor generator battery control module supplies 5 V to the signal circuit and a ground for the low reference circuit. The temperature sensor resistance changes with battery temperature. The resistances of these temperature sensors decrease with temperature. The drive motor generator battery control module uses the battery temperature sensors to control the drive motor generator battery coolant fan and coolant pump operation.
Conditions for Running the DTC
* The vehicle power mode is RUN.
* Accessory 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 10°C (50°F) different from the other 3 sensors.
P0A9D, P0AC7, P0ACC, and P0AEA
The hybrid battery temperature is greater than 85°C (185°F).
P0A9E, P0AC8, P0ACD, and P0AEB
The hybrid battery temperature is less than -40°C (-40°F).
Action Taken When the DTC Sets
* DTCs P0A9C, P0A9D, P0A9E, P0AC6, P0AC7, P0AC8, P0ACB, P0ACC, P0ACD, P0AE9, P0AEB, and P0AEA are Type B DTCs.
* When two or more sensors fail, the drive motor generator battery control module sends a serial data message to the drive motor generator control module to reduce the power use limit to 50 percent and the drive motor battery cooling 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.
Diagnostic Aids
* Battery temperatures can be affected by vehicle load, outside temperature and customer driving conditions. Test drive the vehicle, and attempt to simulate the Freeze Frame/Failure Record conditions this DTC set under.
* An open 5 V reference or ground circuit will have a default scan tool reading of 214°C and 4.99 V.
Reference Information
Schematic Reference
Hybrid Cooling 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, with a scan tool verify the operation of the coolant fan and coolant pump.
2. Observe all four hybrid battery module temperature sensor parameters with a scan tool. The hybrid battery temperature parameters should be between -40 and +85°C (-40 and +185°F) with no more than 15°C (27°F) difference between the four temperature sensors.
Circuit/System Testing
Danger: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.
The High Voltage Disabling procedure will perform the following tasks:
* Identify how to disable high voltage.
* Identify how to test for the presence of high voltage.
* Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.
1. Verify that DTC P0A1F is not set.
• If DTC P0A1F is set, refer to DTC P0A1F, P1A01, P1A05, or P1A06 (P0A1F).
2. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling (High Voltage Disabling).
3. Inspect the inlet air vents for any obstructions or blockages that are external to the drive motor generator battery.
• If inlet air obstructions or blockages are found, remove or repair as needed, Clear the DTC and verify the fan operation.
4. Inspect the vent fan for any damage to the fan blades.
• If fan or blades are damaged, replace the drive motor generator battery assembly.
5. Ignition OFF, connect the 12 V battery.
6. Ignition ON, command the hybrid battery coolant fan speed through the speed ranges using a scan tool. Verify the drive motor battery coolant fan is functional in all speed ranges.
• If the fan does not operate, refer to DTC P0A81 (P0A81).
7. Ignition OFF, disconnect the X 1 harness connector at the drive motor generator battery control module.
Note: The following test must be performed when the battery pack has equalized at room temperature. An increase or decrease in temperature will cause resistance to change and may result in invalid test results.
8. Test the resistance between each of the temperature sensor 5 V reference and low reference circuit terminals listed below. The resistance of each temperature sensor should be within the specified range, and within 500 ohm of each other. Refer to Temperature Versus Resistance (Electrical Specifications).
* Terminal 46 5 V Reference and terminal 41 Low Reference (Sensor 1)
* Terminal 70 5 V Reference and Terminal 6 Low Reference (Sensor 2)
* Terminal 42 5 V Reference and Terminal 40 Low Reference (Sensor 3)
* Terminal 45 5 V Reference and Terminal 22 Low Reference (Sensor 4)
• If not within the specified range, test the drive motor battery sensor module wiring harness for short to voltage, short to ground, or an open/high resistance. If the circuits test normal, replace the drive motor generator battery assembly.
9. 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.
* Drive Motor Battery Sensor Module Wiring Harness Replacement (Drive Motor Battery Sensor Module Wiring Harness Replacement)
* Drive Motor Generator Battery Replacement (Drive Motor Generator Battery Control Module and Bracket Replacement)
* Control Module References (Programming and Relearning) for drive motor generator battery control module replacement, setup and programming