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P0480




DTC P0480 or P0483

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 P0480
- Cooling Fan 1 Control Circuit

DTC P0483
- Cooling Fan System Performance

Circuit/System Description

The hybrid/EV powertrain control module 2 controls the radiator cooling fans. The cooling fans are controlled with a pulse width modulated (PWM) signal. The hybrid/EV powertrain control module 2 diagnoses any faults with the hardwire circuit to the engine control module. The engine control module sends a fan request PWM signal to the hybrid/EV powertrain control module 2 through a hardwire circuit. The hybrid/EV powertrain control module 2 operates in a pass-through mode for the engine control module fan request. The higher the duty cycle the higher the cooling fan speed.

Conditions for Running the DTC

The 12 V battery voltage is greater than or equal to 9 V.

Conditions for Setting the DTC

The hybrid/EV powertrain control module 2 has detected an open, short to ground or short to voltage fault on the fan control circuit.

Action Taken When the DTC Sets

DTC P0480 and P0483 are type B DTCs.

Conditions for Clearing the DTC

DTC P0480 and P0483 are type B DTCs.

Reference Information
Schematic Reference

Engine Cooling Schematics Engine 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

Vehicle in Service Mode, with a scan tool, command the Cooling Fan Motor Command to 90%. Verify that the cooling fan motor speed is greater than 0 RPM and the cooling fans are operating.

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 OFF, disconnect the harness connector at the appropriate G10 cooling fan motor.
2. Test for less than 10 ohm between the ground circuit terminal 2 and ground.

If greater than the specified range, test the ground circuit for an open/high resistance.

3. Vehicle in Service Mode, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.

If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test or replace G10 cooling fan motor.

4. Connect a test lamp between the control circuit terminal 4 and the B+ circuit terminal 1.
5. Command the Cooling Fan Motor Command ON between 10% and 90% with a scan tool. Verify the test lamp changes between dim (10%) and bright (90%).

If the test lamp is always bright , test the control circuit for a short to ground. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
If the test lamp is always dim or OFF, test the control 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, replace the appropriate G10 cooling fan motor.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Cooling Fan and Shroud Replacement Service and Repair
* Control Module References Programming and Relearning for hybrid/EV powertrain control module 2 replacement, programming and setup