NEW STOPLAMP SWITCH & SERVICE PROCEDURE-P/N

*VEHICLES AFFECTED: 1988-90 W CARS

A new stoplamp switch has been released for the 1990 model year, which services all previous model years. The new switch part number is 10180504.

The stoplamp switch replacement and adjustment procedure has been revised. The following procedures should be used when removing, installing or adjusting the stoplamp switch.

This procedure applies to the following Service Manuals Section 5, pages 5-6 and 5-7, please update your Service Manuals.

1990 Chevrolet Lumina Pontiac Grand Prix Oldsmobile Cutlass Supreme Buick Regal

1989 Pontiac Grand Prix Oldsmobile Cutlass Supreme Buick Regal

1988 Pontiac Grand Prix Oldsmobile Cutlass Supreme Buick Regal

PROCEDURE:

STOPLAMP SWITCH -- Figure 1

Remove or Disconnect

1. Air cleaner assembly, if necessary to access battery cables.

2. Negative battery cable.

3. Left side sound insulator panel.

- Slide steering shaft protective sleeve towards the cowl.

4. Air distribution tube and pull down.

5. Retainer clip which holds stoplamp switch to steering column bracket.

6. Switch arm from pedal by pushing the arm over and off the brake pedal pin.

- Release switch by pulling down and releasing top snap clip.

7. Connector positon assurance (CPA) locking pins from the four wire and two wire connector.

8. Two wire connector.

- Two wire connector is optional cruise control equipment.

9. Four wire connector.

10. Switch.

Install or Connect

1. Two wire connector and CPA, if equipped withcruise contro.

2. Switch

- Make sure brake switch is NOT adjusted (metal clip on actuator not engaged with serrations on bottom of carrier).

- Push switch up until seated into the top snap clip.

- Do NOT attach switch arm to pin on brake pedal at this time.

3. Retainer clip which holds stoplamp switch to steering column bracket.

- Push brake pedal down to floor pan and install switch arm over and onto brake pedal pin.

- Pull brake pedal all the way rearward and listen for the stoplamp switch switch to ratchet into the set position. At least three (3) clicks of the ratchet should be heard.

4. Four wire connector and CPA locking pin.

- Position steering shaft protective sleeve.

5. Negative battery cable.

Inspect

- Switch operation

- If the stoplamps do not operate, refer to "Stoplamp Switch Adjustment".

6. Left side sound insulator panel.

7. Air cleaner assembly, if removed.

STOPLAMP SWITCH ADJUSTMENT

Remove or Disconnect - Figure 1 and 2

- Left side sound insulator panel

Adjust

- Stoplamp switch

(a) Depress brake pedal as far as possible and hold.

(b) Using a stiff wire with a hooked end, gently pull the switch set lever forward (toward front of vehicle), and listen for an audible click that indicates release of the automatic adjuster.

IMPORTANT: If no click is heard, release brake pedal and repeat above procedure.

(c) After release of the automatic adjuster, pull brake pedal all the way rearward. Listen for the switch to ratchet into the set positon (setting the stoplamp switch). At least three (3) clicks of the ratchet should be heard.

Inspect - Operation of Stoplamps

(a) Stoplamps should light at maximum brake pedal travel of 32mm (1-1/4 in.) and throughout its travel.

(b) If stoplamps do not light, repeat switch adjustment procedure one more time. If the switch still fails to activate the stoplamps, refer to "Stoplamp Switch Adjustment Check" in BRAKES (Section 5).

Install or Connect

- Left side sound insulator

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.