GM Service Manual Online
For 1990-2009 cars only

    Object Number: 293254  Size: SH

    Caution: The new SIR coil assembly will be centered. Improper alignment of the SIR coil assembly may damage the unit, causing an inflatable restraint malfunction.

  1. Verify the following conditions before centering the SIR coil:
  2. • The wheels on the vehicle are straight ahead.
    • The block tooth (1) of the steering shaft assembly is in the 12 o'clock position.
    • The ignition switch assembly is in the LOCK position.

    Object Number: 603737  Size: SH
  3. If the front (5) of the SIR coil has a centering window (4), and the back side (2) has a spring service lock (1), perform the following steps:
  4. 2.1. Hold the coil with the face up.
    2.2. While depressing the spring service lock, rotate the coil hub clockwise until the coil ribbon stops.
    2.3. Rotate the coil hub slowly, counterclockwise, until the centering window appears yellow and both arrows (3) line up.
    2.4. Release the spring service lock between the locking tab. The SIR coil is now centered.
    2.5. Align the centered SIR coil with the horn tower and slide onto the steering shaft assembly.

    Object Number: 594558  Size: SH
  5. If the front (4) of the SIR coil has a centering window (3) and the back side (1) has NO spring service lock, perform the following steps:
  6. 3.1. Hold the coil with the face up.
    3.2. Rotate the coil hub clockwise until the coil ribbon stops.
    3.3. Rotate the coil hub slowly, counterclockwise until the centering window appears yellow and both arrows (2) line up. This is the CENTER position.
    3.4. While holding the coil hub in the CENTER position, align the coil with the horn tower and slide the coil onto the steering shaft assembly.

    Object Number: 603738  Size: SH
  7. If no centering window is present on the front side (3) of the SIR coil, but a spring service lock (1) is on the back side (2), perform the following steps:
  8. 4.1. Hold the coil with the back side up.
    4.2. While depressing the spring service lock, rotate the coil hub in the direction of the arrow (4) until the coil ribbon stops.
    4.3. Still pressing the spring service lock, rotate the coil hub in the opposite direction 2½ revolutions.
    4.4. Release the spring service lock between the locking tabs. The SIR coil is now centered.
    4.5. Align the centered coil with the horn tower and slide the coil onto the steering shaft assembly.

    Object Number: 603739  Size: SH
  9. If no centering window appears on the front side (2) of the SIR coil and no spring service lock exists on the back side (1), perform the following steps:
  10. 5.1. Hold the coil with the face up.
    5.2. Rotate the coil hub in the direction of the arrow until the coil ribbon stops.
    5.3. Rotate the coil hub, slowly, counterclockwise, for 2½ revolutions. This is the CENTER position.
    5.4. While maintaining the coil hub in the CENTER position, align the centered coil with the horn tower and slide the coil onto the steering shaft assembly.