Preliminary Checks
NOTE:
Always check the fluid level in the brake master cylinder reservoir (2K478) before carrying out the test procedures. If the fluid level is not at the correct level, fill the reservoir using the specified DOT 3 or DOT 4 brake fluid.
NOTE:
Prior to carrying out any diagnosis, make certain that the brake warning indicator is functional.
A change in brake pedal feel is usually the first indicator of a brake system concern. The brake warning indicator in the instrument cluster and the brake fluid level in the brake master cylinder reservoir are also indicators of system concerns.
If a wheel (1007) is locked and the vehicle must be moved, open a bleeder screw at the locked wheel to let out enough fluid to relieve the pressure. Close the bleeder screw. This bleeding operation may release the brakes but will not correct the cause of trouble. If this does not relieve the locked wheel condition, repair the locked components before proceeding.
For low or spongy brake pedal concerns:
- Check and, if necessary, refill the brake master cylinder reservoir.
- Bleed the brake system and retest the brake pedal feel.
For slow or incomplete brake pedal return concern:
- Inspect for binding, damage, correct installation or interference at the brake pedal (2455).
- Check the power brake booster for binding, damage and correct installation.
- Verify customer complaint.