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Home >> Cadillac >> 2018 >> CT6 Plug-In >> Repair and Diagnosis >> Steering >> Power Steering System >> Repair Instructions >> Power Steering Assist Motor Replacement >> Installation Procedure
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Installation Procedure

  1. Use a clean shop rag to clean the power steering assist motor mating surface on the steering gear housing so it is free of old grease and loose particles.
  2. GM3448421Courtesy of GENERAL MOTORS COMPANY

    Install a NEW power steering assist motor seal (1).

    3. NOTE:
    • Do NOT spray on the lithium grease or overspray may occur.
    • The power steering assist motor gear teeth MUST remain grease free.
  3. Add a light film of lithium grease to the nose (2) of the power steering assist motor.
  4. GM4229515Courtesy of GENERAL MOTORS COMPANY

    Inspect the teeth (1) on the power steering assist motor gear and the large steering gear pulley.

    The teeth are directional and the NEW steering gear belt MUST be installed in the proper direction.

  5. Hang the NEW steering gear belt on the large steering gear pulley.
  6. GM4258867Courtesy of GENERAL MOTORS COMPANY
    NOTE:
    • Do NOT pinch or roll the power steering assist motor seal while installing the power steering assist motor into the steering gear housing.
    • Before adding tension to the steering gear belt, ensure the belt is centered on the large steering gear pulley.

    Install the nose of the power steering assist motor (1) into the steering gear housing and slide the steering gear belt onto the nose of the motor.

    Do NOT allow the belt to come into contact with any of the grease in the steering gear housing.

  7. After the power steering assist motor (1) is installed in the steering gear housing and steering gear belt, rotate the motor clockwise, while making sure the screw holes in the motor and slotted holes in steering gear housing are aligned properly.
  8. GM5125462Courtesy of GENERAL MOTORS COMPANY
    NOTE:
    • The space washers will ensure the power steering assist motor is flush with the steering gear housing.
    • After hand tightening the NEW power steering assist motor pivot bolt (2) and the OLD steering gear housing cover bolt (3), ensure the motor can still rotate.

    Install the NEW power steering assist motor pivot bolt (2) and hand tighten.

    9. NOTE:

    The number of spacer washers required will depend on the thickness of the space washers used.

  9. Install spacer washers (1) on the OLD steering gear housing cover bolt (3) and hand tighten.
  10. GM4258864Courtesy of GENERAL MOTORS COMPANY

    Use an open end wrench (1) to rotate the steering gear input shaft (2) 90 degrees in both directions and back to the center position to seat the steering gear belt.

  11. Use the following procedure to verify the steering gear rack is centered:
    1. Measure distance (a) from the top of the steering linkage outer tie rod to the steering gear boot inner clamp on either side of the steering gear rack.
    2. Measure distance (b) from the top of the steering linkage outer tie rod to the steering gear boot inner clamp on the opposite side of the steering gear rack.
    3. Verify both measurement (a) and measurement (b) are equal.
    4. If the measurements are not equal, turn the steering gear input shaft until the measurements are the same.
  12. GM3553405Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    Note the position of the tester microphone (1) in the above illustration.

    Place the body of the GE-50576 - A  tester (1) on a flat surface or secure it to the steering gear housing and position the microphone of the tester 6 mm (0.25 in) from the steering gear belt. NEVER hold the tester by hand while taking measurements or the reading will be inaccurate.

  13. GM4229516Courtesy of GENERAL MOTORS COMPANY

    Use a finger to strum the steering gear belt (1) at the center location between the pulleys 3 times to get an average belt tension measurement.

    1. If the average steering gear belt tension measurement is between 300 - 330 Hz then continue to the next step. If the average of the measurements is lower or higher than the specification, then rotate the power steering assist motor clockwise to tighten the belt or counterclockwise to loosen the belt, and take the average of another set of 3 measurements. Repeat this step until the average of the measurements is within the range specified and then tighten the power steering assist motor pivot bolt to 22 N.m (16 lb ft).
    2. Rotate the power steering gear rack bar 90 degrees counterclockwise from center.
    3. Rotate the power steering gear rack bar 90 degrees clockwise from center.
    4. Re-center the steering gear rack bar.
    5. Recheck the steering gear belt tension using the GE-50576 - A  tester. If the reading is not between 300 - 330 Hz then loosen the power steering assist motor pivot bolt and readjust the belt tension. If the measurement is still within the specified range then continue to the next step.
  14. Remove the OLD steering gear housing cover bolt and space washers.
  15. Use a clean shop rag to clean the steering gear housing cover mating surface on the steering gear housing so it is free of old grease and loose particles.
  16. GM4258873Courtesy of GENERAL MOTORS COMPANY

    Install a NEW steering gear housing cover seal (1) and ensure the seal is seated correctly and that both dowel pins (2) are seated.

  17. GM4258870Courtesy of GENERAL MOTORS COMPANY

    Install the steering gear housing cover (1).

  18. GM4258869Courtesy of GENERAL MOTORS COMPANY

    Install the NEW steering gear housing cover bolts (1) and tighten by hand.

  19. Fig 1: Steering Gear Housing Cover Bolts In Sequence
    GM4258874Courtesy of GENERAL MOTORS COMPANY

    Tighten the steering gear housing cover bolts in the following sequence:

    1. M8 Bolts (1): 22 N.m (16 lb ft)
    2. M6 Bolts (2): 10 N.m (89 lb in)
  20. GM4258865Courtesy of GENERAL MOTORS COMPANY
    CAUTION:

    Ensure the torque sensor wiring harness is fully connected and seated to the electric power steering motor controller module. If the harness connector is not fully engaged, damage to the module will occur when the key is turned on and replacement of the module will be necessary.

    NOTE:

    The torque sensor wiring harness is NOT repairable. Do NOT attempt to repair the harness under any circumstances. If the harness is damaged then the steering gear MUST be replaced.

    Connect the torque sensor wiring harness connector (1) to the power steering assist motor controller module.

    Ensure the connector lock is engaged.

  21. Steering Linkage Inner Tie Rod@ Belt Side - Install - Steering Linkage Inner Tie Rod Replacement 
  22. Remove the steering gear from the vise.
    23. CAUTION:

    During removal and installation, all EPS components including mechanical and/or electrical is extremely susceptible to damage. Dropping or prying on any EPS component may cause internal damage. If damage occurs or a part is dropped, the EPS component must be replaced.

    CAUTION:

    Care must be taken during removal and installation of the Electronic Power Steering (EPS) components to not hit or break the EPS motor/controller module or module harness connectors. If the EPS motor/ controller module or module connectors are damaged, the complete component must be replaced.

  23. Steering Gear - Install - Electric Belt Drive Rack and Pinion Steering Gear Replacement 
  24. Program the power steering control module. Control Module References
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