GM Service Manual Online
For 1990-2009 cars only

When installing the power seat adjusters, verify that both adjusters meet the following qualifications:

    • The adjusters are parallel.
    • The adjusters are in phase with each other. Both adjusters simultaneously reach their maximum horizontal or vertical travel in a given direction.

If the adjusters are out of phase, correct the adjusters using one or both of the following procedures.

Repeat these operations as needed if the adjusters do not appear to be in phase after the test cycle.

Horizontal Travel Adjustment

  1. Operate the seat control switch until one adjuster reaches the full-forward position.
  2. Detach the horizontal drive cable from the adjuster which has reached the full-forward position.
  3. Operate the seat forward until the other adjuster reaches the full-forward position.
  4. Connect the horizontal drive cable.
  5. Verify the horizontal travel of the seat.

Front or Rear Vertical Travel Adjustment

  1. Operate the seat control switch until one adjuster has reached the fully raised position at both the front and the rear vertical travel limits.
  2. Disconnect the front and the rear vertical drive cables from the adjuster which has reached the fully raised position.
  3. Operate the seat control switch until the other adjuster reaches the fully raised position at both the front and the rear vertical travel limits.
  4. Connect the previously removed front and rear vertical drive cables.
  5. Verify the vertical travel of the seat by operating the adjusters through 1 or 2 complete cycles.