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DTC P0C4E

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 P0C4E: Drive Motor 1 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 total offset 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 P0C4E is a Type A DTC.

Conditions for Clearing the DTC

DTC P0C4E 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

Special Tools

DT-44152 Jumper Harness

For equivalent regional tools, refer to Special Tools .

Circuit/System Testing

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

  1. Verify that DTCs P0A3F, P0A40, P0C52, P0C53, P0C5C, P0C5D or P1B03 are not set.
  2. If any of the DTCs are set, refer to DTC P0A3F, P0A40, P0C52, P0C53, P0C5C, P0C5D or P1B03 .
  3. Vehicle OFF, disconnect the X175 harness connector at the transmission.
  4. Install the DT-44152 jumper harness to the harness side only.
  5. Disconnect the X1 harness connector at the T6 power inverter module.
  6. Test for less than 1 Ω between the terminals listed below:
  7. • DT 44152 Terminal L and X1 terminal 1
    • DT 44152 Terminal M and X1 terminal 12
    • DT 44152 Terminal U and X1 terminal 2
    • DT 44152 Terminal T and X1 terminal 13
    • DT 44152 Terminal W and X1 terminal 3
    • DT 44152 Terminal V and X1 terminal 14
    If greater that the specified range, test the signal circuit for an open/high resistance.
  8. If all circuits test normal, replace the drive motor generator position sensor.

Component Testing

  1. Vehicle OFF, disconnect the X175 harness connector at the transmission.
  2. Install the DT-44152 jumper harness to the transmission side only.
  3. Test for 10-25 Ω between the AC circuit at terminal V and the AC circuit at terminal W.
  4. If less than the specified range, test the transmission control wiring harness extension harness circuits for a short-circuit between the AC circuits. If the circuits test normal, replace the drive motor generator position sensor.
    If greater than the specified range, test each transmission control wiring harness extension harness AC circuits for an open-circuit. If the circuits test normal, replace the drive motor generator position sensor.
  5. Test for 15-35 Ω between the signal terminal U and the signal terminal T.
  6. If less than the specified range, test the transmission control wiring harness extension harness circuits for a short-circuit between the signal circuits. If the circuits test normal, replace the drive motor generator position sensor.
    If greater than the specified range, test each transmission control wiring harness extension harness signal circuits for an open-circuit. If the circuits test normal, replace the drive motor generator position sensor.
  7. Test for 15-35 Ω between the signal terminal L and the signal terminal M.
  8. If less than the specified range, test the transmission control wiring harness extension harness circuits for a short-circuit between the signal circuits. If the circuits test normal, replace the drive motor generator position sensor.
    If greater than the specified range, test each transmission control wiring harness extension harness signal circuits for an open-circuit. If the circuits test normal, replace the drive motor generator position sensor.
  9. Test for greater than 10 Ω between the terminals listed below and earth:
  10. • Terminal V
    • Terminal W
    • Terminal U
    • Terminal T
    • Terminal L
    • Terminal M
    If less that the specified value, test the transmission control wiring harness extension harness circuit for a short-circuit to earth. If the circuit tests normal, replace the drive motor generator position sensor.
  11. Test for infinite resistance between the terminals listed below:
  12. • Terminals V and U
    • Terminals V and L
    • Terminals U and L
    If less that the specified value, test the transmission control wiring harness extension harness circuits for a short-circuit between the circuits. If the circuits test normal, replace the drive motor generator position sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Case Cover Assembly Disassemble and Case Cover Assembly Assemble for drive motor generator 1 position sensor replacement.
    • Automatic Transmission Wiring Harness and Output Speed Sensor Removal and Automatic Transmission Wiring Harness and Output Speed Sensor Installation for Wiring Harness Extension Harness replacement
   


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