GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the fuel tank shield, if equipped. Refer to Fuel Tank Shield Replacement .

  3. Object Number: 1234201  Size: SH
  4. Disconnect the motor/encoder electrical connector (1).

  5. Object Number: 743564  Size: SH
  6. Remove the motor/encoder mounting bolts.

  7. Object Number: 743566  Size: SH
  8. Remove the motor/encoder assembly.
  9. Important: When replacing the encoder rotary position sensor, follow steps 6-10. The rotary position sensor is circular with 3 contacts on one side and is positioned behind the motor/encoder baseplate/gasket. The rotary position sensor replacement kit consists of a rotary position sensor, baseplate/gasket, and detailed instruction sheet.

  10. Position the motor on a work bench.

  11. Object Number: 1237683  Size: SH
  12. Release the 4 tabs that retain the motor/encoder plastic baseplate and remove the baseplate/gasket (1).
  13. Discard the old baseplate/gasket, replacement baseplate/gasket provided in rotary position sensor kit.
  14. Important: The motor/encoder rotary position sensor internal wires go to a connector within the motor housing. This internal wire connector does not have a locking tab and is easily disturbed.

  15. Gently lift the motor/encoder rotary position sensor (2) from the motor shaft.
  16. Important: Look at the motor/encoder housing (1) where the rotary position sensor was removed from. Take note of the "Hex" in the housing where the new sensor will seat when properly installed.

  17. Disconnect the rotary position sensor (2) from the wiring harness.

Installation Procedure

    Important: Provided the rotary position sensor was removed, follow steps 1-5 to install the sensor, otherwise proceed to step 6 installing the motor/encoder to the transfer case.

  1. Connect the wiring harness to the rotary position sensor.
  2. Gently insert a suitable tool along side the internal wires and press down on the internal wire connector to ensure the connector is fully installed.

  3. Object Number: 1238219  Size: SH
  4. Properly align the keyway of the rotary position sensor with the motor/encoder shaft as indicated by the center reference line shown in the graphic.

  5. Object Number: 1237683  Size: SH
  6. Ensure that the hex on the rotary position sensor (2) fits in the hex of the motor/encoder housing (3).
  7. Install the motor/encoder baseplate/gasket (1).

  8. Object Number: 743566  Size: SH

    Important: When performing this service procedure, make sure that the motor/encoder unit is flat against the transfer case for proper installation.

  9. Install the motor/encoder to the transfer case.
  10. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 743564  Size: SH
  11. Install motor/encoder mounting bolts to the transfer case.
  12. Tighten
    Tighten the bolts to 16 N·m (12 lb ft).


    Object Number: 1234201  Size: SH
  13. Connect the motor/encoder electrical connector (1).
  14. Install the fuel tank shield, if equipped. Refer to Fuel Tank Shield Replacement .
  15. Lower the vehicle. Refer to Lifting and Jacking the Vehicle .