GM Service Manual Online
For 1990-2009 cars only

Test Descriptions

The number below refers to the step number on the diagnostic table.

  1. Suspension components that are not operating properly may cause a disturbance to the vehicle during application of the brake system.

Step

Action

Yes

No

DEFINITION: Braking action or stopping force sensitive or grabbing and/or more pronounced at the front or at the rear axle. Sensitive or grabbing brakes: Excessive brake jump-in force relative to brake pedal input.

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 hydraulic brake system for the following conditions:
  2. • Improper operation of caliper pistons
    • Kinked, pinched or damaged brake pipe or flexible brake hose
    • Brake fluid leak
    • Improperly functioning proportion valve, if equipped
    • Improper operation of dynamic rear proportion (DRP) system, if equipped
  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 3

3

  1. Inspect the disc brake system for the following conditions:
  2. • Contaminated linings
    • Glazed linings
    • Distorted, cracked or damaged linings
    • Excessively worn linings
    • Aftermarket linings
    • Damaged or excessively worn caliper hardware and/or lining hardware
    • Hard spots, heat checks, blueing discoloration of rotor friction surfaces
    • Glazed 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 4

4

  1. Inspect the suspension system for the following conditions:
  2. • Loose suspension component connections
    • Excessively worn or damaged suspension components
  3. Adjust, repair or replace components as necessary. Refer to Diagnostic Starting Point - Suspension General Diagnosis.

Did you find and correct a condition?

Go to Step 6

Go to Step 5

5

  1. Inspect the brake assist system for the following conditions:
  2. • Binding, bent or damaged pedal pushrod, pedal, or pedal bracket
    • Damaged or improperly operating vacuum booster, if equipped
    • Damaged or improperly operating hydraulic booster, if equipped
  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 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