Road Test: Notes

The technician should have a thorough knowledge of the brake system operation and accepted general braking guidelines in order to detect any problems.

Select a road that is reasonably smooth and level. Gravel or bumpy roads are not suitable because the surface does not allow the tires to grip the road equally. Avoid crowned roads.

A key factor in evaluating brake concerns is the deceleration rate. This varies from vehicle to vehicle and with changes in operating conditions. It is evident how well the brakes are working after just a few applications.

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.
• if the brake pedal is still low or feels spongy, check the brake pedal mounting for looseness and correct installation. Check the brake booster and the brake master cylinder for loose mounting. Correct as necessary and retest the system for normal operation.

For a slow or incomplete brake pedal return concern:

• inspect for binding, damage, correct installation or interference at the brake pedal.
• check the brake booster for binding, damage and correct installation.