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DTC P0C4F

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0C4F: Drive Motor 2 Position Exceeded Learning Limit

Circuit/System Description

The drive motor generator position sensor is monitored by the motor control module. The motor control module monitors the angular position, speed and direction of the drive motor generator rotor based upon the signals of the resolver-type position sensor. The position sensor contains a drive coil, two driven coils and an irregular shaped metallic rotor. The metallic rotor is mechanically attached to the shaft of the drive motor generator. At vehicle ON, the motor control module outputs a 7 volt ac, 10 kHz excitation signal to the drive coil. The drive coil excitation signal creates a magnetic field surrounding the two driven coils and the irregular shaped rotor. The motor control module then monitors the two driven coil circuits for a return signal. The position of the irregular metallic rotor causes the magnetically-induced return signals of the driven coils to vary in size and shape. A comparison of the two driven coils signals allows the motor control module to determine the exact position, speed and direction of the drive motor generator rotor.

Offset is the relationship between the position sensor and the drive motor generator output shaft. When the vehicle is turned OFF, the motor control module attempts to learn the offset of the drive motor position sensor.

Conditions for Running the DTC
    • The vehicle is cycled OFF.
    • Drive motor generator speed is less than 20 RPM.
    • DC High Voltage is greater than 192 V.

Conditions for Setting the DTC
    • The position sensor offset total exceeds 30 degrees during the learning process.
    • The current learned value differs from the previous learned value by greater than 10 degrees.

Action Taken When the DTC Sets

DTC P0C4F is a Type A DTC.

Conditions for Clearing the DTC

DTC P0C4F is a Type A DTC.

Diagnostic Aids
    • The drive motor generator position sensor circuits operate at very low current. Just a few ohms of additional circuit resistance may cause position sensor signal degradation. Extreme care must be taken when probing terminals and manipulating harnesses.
    • The sensor circuit loops are a twisted pair with each pair covered in a foil shield. The shield circuits outside of the transmission are earthed to the drive motor generator power inverter module.
    • Ensure the drive motor generator position sensor harness shield circuits are properly earthed prior to testing.

Reference Information

Schematic Reference

Hybrid Controls Schematics

Connector End View Reference

    •  Component Connector End Views
    •  Inline Harness Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Testing

    Note: You must perform the Component Testing before proceeding with Circuit/System Testing.

  1. Verify that DTC P0A45, P0A46, P0C57, P0C58, P0C61, P0C62, or P1B04 are not set.
    2. ⇒If any of the DTCs are set, refer to DTC P0A45, P0A46, P0C57, P0C58, P0C61, P0C62, or P1B04 .
  2. Vehicle OFF, disconnect the X1 and X2 harness connectors at the transmission.
  3. Disconnect the X1 harness connector at the T6 power inverter module.
  4. Test for less than 1 Ω between the terminals listed below:
    5. • Terminals 20 and X1 terminal 1
    • Terminals 30 and X1 terminal 2
    • Terminals 21 and X1 terminal 3
    • Terminals 31 and X1 terminal 4
    • Terminals 22 and X2 terminal 1
    • Terminals 32 and X2 terminal 1
    ⇒If greater that the specified range, test the signal circuit for an open/high resistance.
  5. If all circuits test normal, replace the drive motor generator 2 position sensor.

Component Testing
  1. Vehicle OFF, disconnect the X1 and X2 harness connectors at the transmission.
  2. Test for 15-25 Ω between the AC circuit at X2 terminal 1 and the AC circuit at X2 terminal 2.
    3. ⇒If not within the specified range, replace the drive motor generator 2 position sensor.
  3. Test for 35-55 Ω between the signal circuit at X1 terminal 3 and the signal circuit at X1 terminal 4.
    4. ⇒If not within the specified range, replace the drive motor generator 2 position sensor.
  4. Test for 35-55 Ω between the signal circuit at X1 terminal 1 and the signal circuit at X1, terminal 2.
    5. ⇒If not within the specified range, replace the drive motor generator 2 position sensor.
  5. Test for greater than 15 Ω between the terminals listed below and earth:
    6. • X1 terminal 1
    • X1 terminal 2
    • X1 terminal 3
    • X1 terminal 4
    • X2 terminal 1
    • X2 terminal 2
    ⇒If less than the specified value, replace the drive motor generator 2 position sensor.
  6. Test for infinite resistance between the terminals listed below:
    7. • X1 terminal 1 and X1 terminal 3
    • X1 terminal 1 and X2 terminal 1
    • X1 terminal 3 and X2 terminal 1
    ⇒If less than the specified value, replace the drive motor generator 2 position sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Drive Motor Generator Position Sensor Stator Removal and Drive Motor Generator Position Sensor Stator Installation for drive motor generator 2 position sensor replacement

   


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