P0C32
DTC P0C32
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 Descriptor
DTC P0C32
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Hybrid/EV Battery Pack Cooling System Performance
Circuit/System Description
The hybrid/EV battery pack cooling fan draws air through the hybrid/EV battery pack to control the temperature of the hybrid/EV battery pack. To operate, the cooling fan receives an enable signal from the starter/generator control module. The enable control is controlled by a discrete high side driver in the starter/generator control module. When the enable control circuit is high, the fan will be enabled. The fan speed is controlled by a fan control circuit in the starter/generator control module, by changing the duty cycle. Maximum fan speed is 3900 RPM.
The hybrid/EV battery pack cooling system consists of the hybrid/EV battery pack cooling fan pulling air through a set of porous ducts within the hybrid/EV battery pack. These ducts direct air through the hybrid/EV battery sections and under the starter/generator control module, where the air passes by various heat sinks and cavities to cool the internal electronic components. The performance diagnostic for the hybrid battery pack cooling fan is a functional check for the fan. The fan control feature uses the outcome of this diagnostic to take emissions related remedial actions. The hybrid/EV battery pack cooling system performance diagnostic determines if the cooling system is providing the expected amount of conditioning. The hybrid/EV battery pack cooling fan not spinning at the commanded speed or a blocked duct are examples of conditions of reduced performance.
The starter/generator control module uses a temperature model to predict the temperature of the 14 volt power module, an internal electronic component of the starter/generator control module. The starter/generator control module compares this predicted temperature to the 14 volt power module temperature sensor 1. With the hybrid/EV battery pack cooling fan operating, the predicted 14 volt power module temperature and the 14 volt power module temperature sensor 1 should be nearly the same.
Conditions for Running the DTC
* Ignition is RUN or CRANK
* No power mode DTCs are set
* None of the following DTCs are set: P0A81, P0A84, P0A85, P0A88, P0A89, P0AAD, P0AAE, P0AAF, P0D64, P0D65, P0D66, P1A90, P1A92, P1AE8, P1AE9, P1AEC, U182A
* Hybrid battery pack temperature is greater than -10°C (14°F)
* The battery pack inlet temperature sensor is greater than -10°C (14°F)
* The battery pack cooling fan speed is greater than 29%
* 14 volt power module power is greater than 0.1 Kwatt
* The number of non-faulted battery cell temperature sensors is greater than 4
* Propulsion system is active for a minimum of 150 seconds
* Within the past 180 seconds, the 14 volt power module mower has not changed more than 0.6 Kwatts over a time of 30 seconds
Conditions for Setting the DTC
The predicted temperature of the hybrid/EV battery pack is more than 15°C (27°F) higher or lower than the actual measured 14 volt power module temperature sensor 1
Action Taken When the DTC Sets
DTC P0C32 is a type B DTC
Conditions for Clearing the DTC
DTC P0C32 is a type B DTC
Reference Information
Schematic Reference
Hybrid Cooling Schematics Hybrid Cooling Schematics
Connector End View Reference
Component Connector End Views Connector End Views By Name
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
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.
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 exactly as written may result in serious injury or death.
Danger:
The eAssist battery pack assembly will utilize an exchange program. Please consult the most recent revision of bulletin/PI# PIC5520, available in Service Information♦(SI), for a list of approved eAssist battery pack assembly service procedures. Components that may be removed and serviced without exchanging the complete battery pack assembly are identified in the bulletin/PI. Please contact the GM Technical Assistance Center (1-877-446-8227) if you have any questions.
1. Visually inspect the inlet and outlet of the hybrid/EV battery pack cooling fan ducts.
2. Verify the inlet and outlet are free of any debris or obstructions that will limit airflow through the duct.
• If any debris or obstructions are found
Remove the obstruction to allow proper airflow and allow the hybrid/EV battery pack to cool before retesting.
• If no debris or obstructions are found
3. Verify the hybrid/EV battery pack cooling fan ducts are properly secured and are not crimped, crushed, or deformed in a manner that will limit airflow through the duct.
• If the ducts are unsecured or damaged
Repair or replace as necessary and allow the hybrid/EV battery pack to cool before retesting.
• If the ducts are properly secured and undamaged
4. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the G14 hybrid/EV battery pack cooling fan. It may take up to 2 minutes for all vehicle systems to power down.
5. Test for less than 10 ohms between the ground circuit terminal 1 and ground.
• If 10 ohms or greater
1. Ignition OFF.
2. Test for less than 2 ohms between the ground circuit terminal 1 and ground.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 10 ohms
6. Ignition ON.
7. Verify a test lamp illuminates between the B+ circuit terminal 5 and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Ignition OFF.
2. Test for less than 2 ohms in the B+ circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Ignition OFF.
2. Test for infinite resistance between the B+ circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the G14 hybrid/EV battery pack cooling fan.
• If the test lamp illuminates
8. Verify that the hybrid/EV battery pack cooling fan speed increases and decreases as the Hybrid Battery Fan Speed is commanded from 10%-90% with a scan tool.
• If the fan speed does not change
Replace the G14 hybrid/EV battery pack cooling fan.
• If the fan speed changes
9. Monitor the airflow at the intake duct and outlet duct while commanding the Hybrid Battery Fan Speed from 10%-90% with a scan tool. The actual airflow should increase as the fan speed is increased.
• If the airflow does not increase
1. Ignition OFF, disable the high voltage at the A4 hybrid/EV battery pack. Refer to High Voltage Disabling High Voltage Disabling.
2. Remove any debris or obstructions that may limit airflow in the cooling ducts through the A4 hybrid battery assembly and the heat sink under the K59 starter/generator control module.
• If the airflow increases
10. Verify the scan tool battery energy control module Battery Temperature parameters are all be between -39° and 60°C (-38.2 and 140°F).
• If not between -39° and 60°C (-38.2 and 140°F)
Replace the C4A hybrid/EV battery section 1 and C4B hybrid/EV battery section 2.
• If between -39° and 60°C (-38.2 and 140°F)
11. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Generator Battery Replacement Generator Battery Replacement
* Drive Motor Battery Cooling Blower Outlet Duct Replacement Drive Motor Battery Cooling Blower Outlet Duct Replacement
* Drive Motor Battery Cooling Air Outlet Duct Replacement Drive Motor Battery Cooling Air Outlet Duct Replacement
* Drive Motor Battery Cooling Air Inlet Upper Duct Replacement Drive Motor Battery Cooling Air Inlet Upper Duct Replacement
* Drive Motor Battery Cooling Blower Replacement Drive Motor Battery Cooling Blower Replacement
* Control Module References Programming and Relearning for starter/generator control module replacement, programming, and setup