GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

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 stop lamp switch for proper adjustment to ensure that the brake pedal is fully releasing. Refer to Stop Lamp Switch Adjustment in Lighting Systems.
  2. Inspect the cruise control release switch, if equipped, for proper adjustment to ensure that the brake pedal is fully releasing. Refer to Cruise Release Switch Adjustment in Cruise Control.

Did you find and correct a condition?

Go to Step 11

Go to Step 3

3

Inspect the drum brake system for proper operation. Refer to Drum Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 11

Go to Step 4

4

Inspect the park brake system for proper operation. Refer to Park Brake System Diagnosis in Park Brake.

Did you find and correct a condition?

Go to Step 11

Go to Step 5

5

Inspect the disc brake system for proper operation. Refer to Disc Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 11

Go to Step 6

6

  1. Separate the brake booster pushrod from the brake pedal. Refer to Brake Pedal Assembly Replacement .
  2. Inspect the brake corners to determine if the brake drag condition is still present.

Do the brake corners still exhibit the brake drag condition?

Go to Step 8

Go to Step 7

7

Replace the brake pedal assembly. Refer to Brake Pedal Assembly Replacement .

Did you complete the replacement?

Go to Step 11

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8

  1. Separate the master cylinder from the brake booster. Do not disconnect any brake pipes. Refer to Master Cylinder Replacement .
  2. Inspect the brake corners to determine if the brake drag condition is still present.

Do the brake corners still exhibit the brake drag condition?

Go to Step 10

Go to Step 9

9

Replace the brake booster assembly. Refer to Power Vacuum Brake Booster Replacement .

Did you complete the replacement?

Go to Step 11

--

10

Inspect the hydraulic brake system for proper operation. Refer to Hydraulic Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 11

Go to Diagnostic Starting Point - Hydraulic Brakes

11

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

Is the condition still present?

Go to Step 2

System OK