P0CF1
DTC P0CEF-P0CF1
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 P0CEF
- Hybrid/EV Electronics Coolant Temperature Sensor Performance
DTC P0CF0
- Hybrid/EV Electronics Coolant Temperature Sensor Circuit Low Voltage
DTC P0CF1
- Hybrid/EV Electronics Coolant Temperature Sensor Circuit High Voltage
Circuit/System Description
The hybrid/EV electronics has a coolant temperature sensor. The hybrid/EV electronics coolant temperature sensor is located in the coolant radiator. The temperature sensor is a variable resistor that measures the temperature of the hybrid/EV electronics coolant. The hybrid/EV electronics coolant temperature sensor resistance changes with battery coolant 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 hybrid/EV electronics coolant temperature sensor to determine the hybrid/EV electronics temperature to control the hybrid/EV electronics cooling operation.
Conditions for Running the DTC
P0CEF
* The 12 V battery voltage is greater than or equal to 9 V.
* Ignition is not in CRANK.
* No fault on power inverter max temperature sensor.
* Hybrid/EV electronics coolant pump off soak time is greater than 6 hours OR hybrid/EV electronics coolant pump off soak time is greater than 6 hours and has been enabled for less than 15 seconds.
* None of the following DTCs are set; P0606, P0CF1, P0CF0, P0CE9, P0CED, P0A2D, P0A2C, P0A2B, P0A2F, P0A31, P0A32, P0A33, or P0A35.
OR
* The 12 V battery voltage is greater than or equal to 9 V.
* Ignition is in RUN.
* The propulsion system active.
* The hybrid/EV electronics coolant pump is enabled.
* The hybrid/EV electronics coolant pump speed (duty cycle) is between within 30% and 90%.
* None of the following DTCs are set; P0CF1, P0CF0, P0CE9, P0CED, P1ED6, P1ED7, P1ED8, P0A2D, P0A2C, P0A2B, P0A2F, P0A31, P0A32, P0A33, or P0A35.
OR
* The 12 V battery voltage is greater than or equal to 9 V.
* Ignition is OFF.
* The hybrid/EV electronics coolant pump is enabled.
* The hybrid/EV electronics coolant pump speed (duty cycle) is between within 30% and 90%.
* The vehicle is in charge mode.
* None of the following DTCs are set; P0CF1, P0CF0, P0CE9, P0CED, P1ED7, P1ED6, or P1ED8.
P0CF0 and P0CF1
* The ignition is ON.
* The 12 V battery voltage is greater than or equal to 9 V.
Conditions for Setting the DTC
P0CEF
* The coolant temperature does not fall within 30°C (86°F) of the Drive Motor A Inverter Temperature or Drive Motor B Inverter Temperature (the higher of the two readings).
OR
* The coolant temperature does not fall within 20°C (68°F) and the battery charger temperature is 10°C (50°F).
OR
* The coolant temperature does not fall within 10°C (50°F) of the battery charger temperature.
P0CF0
The hybrid/EV electronics coolant temperature is greater than 87.5°C (189.5°F).
P0CF1
The hybrid/EV electronics temperature is less than -40°C (-40°F).
Action Taken When the DTC Sets
DTC P0CEF-P0CF1 are type B DTCs.
Conditions for Clearing the DTC
DTC P0CEF-P0CF1 are type B DTCs.
Diagnostic Aids
* Low or no coolant in the system may set a DTC P0CF0.
* An inoperative hybrid/EV electronics coolant pump may set a DTC P0CEF.
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
Circuit/System Verification
Observe the scan tool hybrid/EV powertrain control module 2 Hybrid Electronics Coolant Temperature parameter. The readings should be between -39 and +85°C (-38.2 and +185°F).
Circuit/System Testing
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 (1-877-446-8227) if you have any questions.
1. Vehicle in Service Mode, verify that DTC P0CE9 or P0CED is not set.
• If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Vehicle OFF, disconnect the harness connector at the B202 hybrid/EV electronics coolant temperature sensor.
3. Vehicle OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 ohm between the low reference circuit terminal 2 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
4. Vehicle in Service Mode, verify the scan tool Hybrid Electronics Coolant Temperature is less than -35 °C (-38.2 °F).
• If greater than the specified range, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool Hybrid Electronics Coolant Temperature parameter is greater than 127°C (260.6°F).
• If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
6. If all circuits test normal, test or replace the B202 hybrid/EV electronics coolant temperature sensor.
Component Testing
1. Vehicle OFF, disconnect the harness connector at the B202 hybrid/EV electronics coolant temperature sensor.
2. Test for 54-75.5k ohm at approximately 21.11°C (70°F) between the signal terminal and the low reference terminal.
• If not within the specified range, replace the B202 hybrid/EV electronics coolant temperature sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Coolant Temperature Sensor Replacement Coolant Temperature Sensor Replacement
* Control Module References Programming and Relearning for hybrid/EV powertrain control module 2 replacement, programming and setup