GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Hydraulic Brake Diagnostic System Check performed?

--

Go to Step 2

Go to the Hydraulic Brake Diagnostic System Check

2

Perform the brake pedal travel measurement procedure. Refer to Brake Pedal Travel .

Does the brake pedal travel exceed the specified measurement?

--

Go to Step 3

System OK

3

Inspect the brake linings for the following:

    • Excessive wear
    • Contaminated lining material
    • Uneven wear
    • Glazing
    • Abuse
    • Incorrect lining material

Refer to Brake Pad Inspection in Disc Brakes.

Do any of the above conditions exist?

--

Go to Step 4

Go to Step 5

4

Replace the brake linings as necessary.

    • Refer to Front Disc Brake Pads Replacement in Disc Brakes.
    • Refer to Brake Shoe Replacement in Drum Brakes.

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

5

Inspect the brake rotors for the following:

    • Hot spots
    • Scored rotor surface
    • Grooved rotor surface
    • Excessive lateral runout

Refer to Brake Rotor Lateral Runout Check in Disc Brakes

Do any of the above conditions exist?

--

Go to Step 6

Go to Step 7

6

Resurface or replace the brake rotor as necessary. Refer to Brake Rotor Refinishing or Front Brake Rotor Replacement in Disc Brakes.

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

7

Are the rear brakes improperly adjusted?

--

Go to Step 8

Go to Step 9

8

Adjust the rear brakes. Refer to Drum Brake Adjustment in Drum Brakes.

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

9

Inspect the brake assembly for missing or loose attachments. Refer to Brake Pad Inspection in Disc Brakes

Are there any missing or loose attachments?

--

Go to Step 10

Go to Step 11

10

Repair or replace the components as necessary.

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

11

Inspect calipers and wheel cylinders for leakage.

Are any of the components leaking?

--

Go to Step 12

Go to Step 13

12

Replace the leaking components.

    • Repair or replace the FRONT brake calipers. Refer to Front Brake Caliper Overhaul or Front Brake Caliper Replacement in Disc Brakes.
    • Repair or replace the REAR brake wheel cylinders. Refer to Wheel Cylinder Overhaul or Wheel Cylinder Replacement in Drum Brakes.

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

13

Inspect the hydraulic brake system for leaks. Refer to Brake Fluid Leak or Brake Hose Inspection.

Is there any sign of leakage?

--

Go to Step 14

Go to Step 15

14

Repair or replace the components as necessary.

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

15

Inspect the master cylinder for leakage. Refer to Brake Fluid Leak .

Is the master cylinder leaking?

--

Go to Step 16

Go to Step 17

16

Replace the master cylinder. Refer to Brake Modulator/Master Cylinder Assembly Replacement

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

17

Inspect the brake system for air. Refer to Hydraulic Brake System Bleeding .

Is there air in the system?

--

Go to Step 18

Go to Step 19

18

Bleed the brake system. Refer to Hydraulic Brake System Bleeding .

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

19

Inspect the brake fluid for contamination. Refer to Master Cylinder Reservoir Filling .

Is the brake fluid contaminated?

--

Go to Step 20

Go to Step 21

20

Replace all of the hydraulic brake system rubber components.

  1. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .
  2. Replace the ABS modulator. Refer to Brake Modulator Replacement in Antilock Brake System.
  3. Repair or replace the master cylinder. Refer to Master Cylinder Overhaul .
  4. Replace the front brake hoses. Refer to Front Brake Hose Replacement .
  5. Replace the rear brake hoses. Refer to Rear Brake Hose Replacement .
  6. Repair or replace the FRONT brake calipers. Refer to Front Brake Caliper Overhaul or Front Brake Caliper Replacement in Disc Brakes.
  7. Repair or replace the REAR brake wheel cylinders. Refer to Wheel Cylinder Overhaul or Wheel Cylinder Replacement in Drum Brakes.
  8. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .

Is the repair complete?

--

Go to the Hydraulic Brake Diagnostic System Check

--

21

Verify the proper brake system operation.

Does the original condition still exist?

--

Go to Step 1

System OK