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 with specified brake fluid.

NOTE: Prior to carrying out any diagnosis, make certain that the brake warning indicator is functional. See BRAKE SYSTEM .

A change in brake pedal feel is usually the first indicator of a brake system concern. The change may only be normal ABS function, but is sufficient cause for further investigation. 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 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.