GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: Brake pedal requires an increased amount of input from the driver to obtain good braking action and/or stopping distance is increased.

1

Were you sent here from the Hydraulic Brake Symptom table?

Go to Step 2

Go to Diagnostic Starting Point - Hydraulic Brakes

2

  1. Inspect the brake assist system for the following conditions:
  2. • Vacuum leaks, if equipped with vacuum power assist
    • Power steering fluid leaks, if equipped with hydraulic power assist
    • Lack of lubrication, binding or excessively worn pushrod or pedal pivots or pivot bushings
    • Bent or damaged pedal pushrod, pedal, or pedal bracket
    • Damaged or improperly operating brake booster assembly
  3. Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis .

Did you find and correct a condition?

Go to Step 6

Go to Step 3

3

  1. Inspect the hydraulic brake system for the following conditions:
  2. • Binding caliper pistons
    • Binding wheel cylinder pistons, if equipped
    • Internally damaged flexible brake hoses; hindering fluid flow
    • External brake fluid leaks
    • Kinked or damaged flexible brake hoses and/or pipes
    • Internal brake fluid leaks; improperly operating master cylinder
    • Poor brake fluid quality; low boiling point
  3. Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 6

Go to Step 4

4

  1. Inspect the disc brake system for the following conditions:
  2. • Excessively worn linings
    • Glazed linings
    • Cracked, distorted or damaged linings
    • Contaminated linings
    • Binding, damaged or excessively worn caliper hardware and/or lining hardware
    • Lack of lubrication or excessive corrosion on metal to metal contact surfaces
    • Excessively worn or corroded rotor friction surfaces
    • Glazed rotor friction surfaces
    • Hard spots, heat checks, blueing discoloration of rotor friction surfaces
  3. Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 6

Go to Step 5

5

  1. Inspect the drum brake system, if equipped, for the following conditions:
  2. • Excessively worn linings
    • Improper adjustment or improper adjuster operation
    • Glazed linings
    • Cracked, distorted or damaged linings
    • Contaminated linings
    • Out of round or damaged drum
    • Bell-mouth or barrel-shaped drum friction surface
    • Hard spots, heat checks, blueing discoloration of drum friction surface
    • Lack of lubrication on backing plate
    • Excessive dust or foreign matter in drum
  3. Adjust, repair or replace components as necessary. Refer to Drum Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 6

Go to Diagnostic Starting Point - Hydraulic Brakes

6

  1. Install or connect components that were removed or disconnected during diagnosis.
  2. Road test the vehicle in order to confirm proper operation. Refer to Brake System Vehicle Road Test .

Is the condition still present?

Go to Step 2

System OK