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P0C08




DTC P0C05 or P0C08

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 P0C05
- Drive Motor 1 Phase U-V-W Circuit

DTC P0C08
- Drive Motor 2 Phase U-V-W Circuit

Circuit/System Description

Each drive motor is controlled by a motor control module. The drive motor utilize 3 phase AC electricity. The drive 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 is connected at a single, central point. The motor control modules monitor a current sensor connected to each drive motor generator phase. The current sensor is part of the drive motor assembly and is not serviced separately. The motor control module is part of the drive motor generator power inverter module and is not serviced separately.

Conditions for Running the DTC

* The Hybrid Wakeup circuit is active.
* The motor control module has applied current to the drive motor generator.

Conditions for Setting the DTC

The motor control module detects at least one U-V-W phase current sensor is less than 9 A.

Action Taken When the DTC Sets

* DTCs P0C05 and P0C08 are Type A DTCs.
* Propulsion will be disabled.

Conditions for Clearing the DTC

DTCs P0C05 and P0C08 are Type A DTCs.

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 at the drive motor generator power inverter module cable connections.
2. Remove the 3-phase cable assembly from the drive motor generator power inverter module distribution box. Refer to Drive Motor Generator Rotor and Stator Removal - Unit A 11. Drive Motor Generator Rotor and Stator Removal - Unit A and Drive Motor Generator Rotor and Stator Removal - Unit B 18. Drive Motor Generator Rotor and Stator Removal - Unit B.
3. Test for infinite resistance between the Phase Terminals listed below and ground for each phase of the appropriate M15 drive motor generator:

Drive Motor 1
* X7 terminal phase U
* X8 terminal phase V
* X9 terminal phase W

Drive Motor 2
* X10 terminal phase U
* X11 terminal phase V
* X12 terminal phase W

• If less than the specified range, disconnect the 3-phase cable assembly from the transmission. Refer to Drive Motor Generator Rotor and Stator Removal - Unit A 11. Drive Motor Generator Rotor and Stator Removal - Unit A and Drive Motor Generator Rotor and Stator Removal - Unit B 18. Drive Motor Generator Rotor and Stator Removal - Unit B. Ensure the terminals are not contacting chassis ground. Test for infinite resistance between Phase Terminals and ground. If the circuit tests normal, replace the M15 drive motor generator.
• If less than infinite resistance is measured, replace the generator control module 3-phase cable assembly.

4. If infinite resistance is measured, replace the T6 drive motor generator power inverter module.

Repair Instructions

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

* Drive Motor Generator Rotor and Stator Removal - Unit A 11. Drive Motor Generator Rotor and Stator Removal - Unit A for Drive Motor 1, 3-Phase Cable Assembly replacement
* Drive Motor Generator Rotor and Stator Removal - Unit B 18. Drive Motor Generator Rotor and Stator Removal - Unit B for Drive Motor 2, 3-Phase Cable Assembly replacement
* Control Module References Control Module References for Drive Motor Generator Power Inverter Module replacement, setup, and programming.

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