Check brake pedal height, and see if pulling up on the pedal gets rid of the brake lights staying on.
Maybe the lines have to be bled to get rid of air in the brake lines.
Or, the rear brakes should be adjusted tighter.
If this is not the problem, maybe adjusting the brake light switch will help.
1989-93 Pick-Up and Ramcharger Models
WITHOUT SPEED CONTROL
- Push and hold the brake pedal in the applied position.
- Push the switch forward until fully seated against the bracket.
- Release the brake pedal.
- Lightly pull the brake pedal rearward until the master cylinder pushrod bottoms against its internal stop. The switch plunger is now set at its proper clearance.
WITH SPEED CONTROL
- Loosen the switch-to-pedal bracket screw and slide the switch away from the pedal arm.
- Push the pedal down by hand and allow it to return on its own to the free-hanging position. Do not pull it back!
Fig. 1: Brake light switch adjustment specifications - 1989-93 models
- Slide the switch towards the pedal until there is a gap of 0.140 in. (3.5mm) between the plunger and pedal arm.
NOTE: The pedal must not move when measuring the gap.
- Tighten the switch screw to 82 inch lbs. (9 Nm). Recheck the gap.
1994-96 Pick-Up Models
- Push the switch through the clip in the mounting bracket until it is seated against the bracket. The pedal will move forward slightly.
- Gently pull back on the pedal as far as it will go. The switch will ratchet backwards to the correct position.
This procedure calls for setting the switch prior to installation. Installation directions are included in this one procedure.
- Preset the switch in the following manner:
- Pull the switch plunger all the way out until it is fully extended.
- Push the switch plunger inward 4 detent positions (clicks). This will provide the preset position for the switch installation. The plunger will extend approximately 0.55 in. (14mm) out of the housing at this setting.
- Connect the harness wires to the switch.
- Press and hold down the brake pedal.
- Install the switch. Align the tab with the notch, then insert the switch and turn clockwise about 30°to lock it in place.
Do not use excessive force when setting the brake pedal switch or damage to the switch could result.
- Release the brake pedal, then LIGHTLY pull the pedal fully rearward. The pedal will set the switch to the correct depth.