P0A7E
DTC P0A7E
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0A7E
- Hybrid/EV Battery Pack High Temperature
Circuit/System Description
The hybrid/EV battery pack has 9 hybrid/EV battery temperature sensors. The temperature sensor is a variable resistor that measures the temperature of the hybrid/EV battery cell groups. The hybrid/EV battery interface control module supplies 5 V to the signal circuit and a ground for the low reference circuit. The hybrid/EV 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 hybrid/EV powertrain control module 2 uses the battery temperature sensors to determine the hybrid/EV battery module temperature to control the battery cooling system operation.
Conditions for Running the DTC
* The hybrid/EV powertrain control module 2 and hybrid/EV battery energy control module are awake and communicating.
* None of the following DTCs are set: P0A9C, P0A9D, P0A9E, P0AC6, P0AC7, P0AC8, P0ACB, P0ACC, P0ACD, P0AE9, P0AEA, P0AEB, P0BC3, P0BC4, P0BC5, P0C34, P0C35, P0C36, P0C7D, P0C7E, P0C7F, P0C82, P0C83, P0C84, P0C89, P0C8A, P0C8B, P1E8E, P1E8F, P1E90, P1E91, P1E93, P1E94, P1E95, P1E96, P1E97, P1E99, P1E9A, P1E9B, P1E9C, P1E9D, P1E9F, P1EA0, P1EA1, P1EA2, P1EA3, P1EA5, P1EB1, P1EB2, P1EB3, P1EB4, P1EB5, U2401, U2603, U2604, U2605, U2606.
Conditions for Setting the DTC
The maximum sensed temperature in the hybrid/EV battery is greater than 73.5°C (164.3°F).
Action Taken When the DTC Sets
* DTC P0A7E is a type A DTC.
* All of the battery contactors will open.
Conditions for Clearing the DTC
DTC P0A7E is a type A DTC.
Reference Information
Schematic Reference
Hybrid Cooling Schematics Hybrid Cooling Schematics
Connector End View Reference
Component Connector End Views Hybrid/EV Battery Pack X1
Description and Operation
Hybrid Cooling System Description and Operation Hybrid Cooling System Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Special Tools
* EL-48900 - HEV Safety Kit
* EL-48571-25 - High Voltage Battery Pin Out Box
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
Vehicle in Service Mode, observe the scan tool hybrid/EV powertrain control module 2 Maximum Hybrid Battery Module Temperature. The readings should be between -39 and +60°C (-38.2 and +140°F).
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 includes the following steps:
* 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.
Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:
* Safety glasses with appropriate side shields when within 15 meters (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 with leather protectors at all times when working with the high voltage battery assembly, whether the system is energized or not.
Failure to follow the procedures may result in serious injury or death.
Danger: The Volt Battery Pack will utilize an exchange program. Please consult the most recent revision of bulletin/PI #PIP4841, available in Service Information (SI), for a list of approved Volt Battery Pack service procedures. Components that may be removed and serviced without exchanging the complete battery pack are identified in the bulletin/PI. Please contact the GM Technical Assistance Center if you have any questions.
1. Verify that DTC P0A9C-P0A9E, P0AC6-P0ACD, P0AE9-P0AEB, P0BC3-P0BC5, P0C34-P0C36, P0C7D-P0C8B, P0C43-P0C45, P0C47, P0C4A, P0CD6, P0CD7, P0CD8, P0CE0-P0CE3, P0CE6, P0CE7, P0CE9, P0CED, P148A-P148C, P1EC6-P1EC8, or P1E8C is not set.
• If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Vehicle OFF, disable the high voltage at the A4 hybrid/EV battery pack. Refer to High Voltage Disabling High Voltage Disabling.
3. Remove the A4 hybrid/EV battery pack from the vehicle. Refer to Drive Motor Battery Replacement and Shipping Preparation (Volt) Procedures
4. Remove the A4 hybrid/EV battery pack cover. Refer to Drive Motor Battery Cover Replacement Drive Motor Battery Cover Replacement
5. Connect the battery tray ground straps with a jumper to chassis ground.
Note: Do not leave the EL-48571-25 connected to the orange hybrid/EV battery interface control module harness or leave the orange hybrid/EV battery interface control module harness disconnected from the hybrid/EV battery interface control module for more than one hour.
Leaving the EL-48571-25 connected to the orange hybrid/EV battery interface control module harness or leaving the orange hybrid/EV battery
interface control module harness disconnected from the hybrid/EV battery interface control module for more than one hour will result in a unrecoverable unbalanced hybrid/EV battery section.
Note: Use the schematics to identify the correct hybrid/EV battery interface control module and battery section.
6. Disconnect the harness connector at the appropriate K112 hybrid/EV battery interface control module harness connector.
7. Connect the EL-48571-25 - high voltage battery pin out box.
8. Insert the DMM probes into the EL-48571-25 test cavities.
9. Test for 14-20k ohms at 21.11°C (70°F) between each of the signal circuit and low reference circuit terminals at each orange harness connector for all of the K112 hybrid/EV battery interface control modules. Refer to EL-48571 High Voltage Battery Pin Out Box Reference Initial Inspection and Diagnostic Overview. The resistance of each temperature sensor should be within the specified range, and within 1k ohms of each other.
• If not within the specified range, test the signal circuit and low reference circuits for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the appropriate C4 hybrid/EV battery section.
10. If all circuits test normal, replace the appropriate K112 hybrid/EV battery interface control module and C4 hybrid/EV battery section.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Auxiliary Battery Wiring Harness Replacement (Module Harness 2) Auxiliary Battery Wiring Harness Replacement (Module Harness 2)Auxiliary Battery Wiring Harness Replacement (Module Harness 3) Auxiliary Battery Wiring Harness Replacement (Module Harness 3)Auxiliary Battery Wiring Harness Replacement (Module Harness 4) Auxiliary Battery Wiring Harness Replacement (Module Harness 4)Auxiliary Battery Wiring Harness Replacement (Module Harness 1) Auxiliary Battery Wiring Harness Replacement (Module Harness 1)
* Cell Battery Replacement (Section 3) Cell Battery Replacement (Section 3)Cell Battery Replacement (Section 1) Cell Battery Replacement (Section 1)Cell Battery Replacement (Section 2) Cell Battery Replacement (Section 2)- C4 hybrid/EV battery section
* Drive Motor Battery Replacement and Shipping Preparation (Volt) Procedures- A4 hybrid/EV battery pack
* Control Module References Programming and Relearning for hybrid/EV battery interface control module replacement, programming and setup