P0C20
DTC P0C20
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 P0C20
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Auxiliary Transmission Fluid Pump Phase U-V-W Circuits
Circuit/System Description
The power inverter module, often referred to as the drive motor generator power inverter module, contains three motor control modules and the hybrid powertrain control module. Two of the motor control modules operate their respective drive motor generator based upon drive motor generator power inverter module commands. The third motor control module controls the Auxiliary Transmission Fluid Pump Motor. The motors utilize 3 phase AC electricity. The motor stator coil is comprised of three phase circuits. The phase circuits are identified as phase U, phase V, and phase W. The U-V-W phase circuits are connected in a wye configuration. This means each phase in the motor stator is connected at a single, central point. The motor control modules monitor a current sensor connected to each motor phase. The current sensors are part of the motor control module assembly and is not serviced separately. The motor control modules are part of the power inverter module and are not serviced separately.
Conditions for Running the DTC
* The vehicle is ON.
* The motor control module has applied current to the auxiliary transmission fluid pump motor.
Conditions for Setting the DTC
The motor control module detects at least one U-V-W phase current sensor is less than 1.0 A.
Action Taken When the DTC Sets
* DTC P0C20 is a Type A DTC.
* Vehicle propulsion will be disabled.
Conditions for Clearing the DTC
DTC P0C20 is a Type A DTC.
Reference Information
Schematic Reference
Hybrid Controls Schematics Hybrid Controls Schematics
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
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. Perform the High Voltage Disabling High Voltage Disabling procedure for servicing the T6 power inverter module assembly or T12 Transmission.
2. Disconnect the X8 connector from the T6 power inverter module.
3. Test for infinite resistance between the terminals listed below and ground for each phase of the G5 auxiliary transmission fluid pump:
* Terminal 1 phase U
* Terminal 2 phase V
* Terminal 3 phase W
• If less than the specified value, replace the G5 auxiliary transmission fluid pump.
4. Test for less than 0.5 ohm resistance between the terminals listed below and ground for each phase of the G5 auxiliary transmission fluid pump:
* Terminal 1 phase U to Terminal 2 phase V
* Terminal 1 phase U to Terminal 3 phase W
* Terminal 2 phase V to Terminal 3 phase W
• If greater than the specified value, replace the G5 auxiliary transmission fluid pump.
5. Replace the T6 power inverter module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Auxiliary Fluid Pump Motor and Fluid Pump Disassemble Auxiliary Fluid Pump Motor and Fluid Pump Disassemble and Auxiliary Fluid Pump Motor and Fluid Pump Assemble Auxiliary Fluid Pump Motor and Fluid Pump Assemble for Auxiliary Transmission Fluid Pump replacement
* Control Module References Programming and Relearning for Drive Motor Generator Power Inverter Module, also called the power inverter module, replacement, programming, and setup.