GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Hydraulic Brake Diagnosis System Check performed?

--

Go to Step 2

Go to Hydraulic Brake Diagnostic System Check

2

Inspect the disc brake rotors for the following conditions:

    • Hot spots
    • Scored rotor surface
    • Grooved rotor surface
    • Excessive surface variations

Refer to the following procedures:

    •  Brake Rotor Thickness Variation Check in Disc Brakes
    •  Brake Rotor Lateral Runout Check in Disc Brakes
    •  Brake Rotor Tolerance in Disc Brakes

Do any of the above conditions apply?

--

Go to Step 4

Go to Step 3

3

  1. Refinish the brake rotor. Refer to Brake Rotor Refinishing in Disc Brakes.
  2. Inspect the thickness of the brake rotor. Refer to Component Specifications in Disc Brakes.
  3. If refinishing the brake rotor results in a thickness that is less than the thinnest (Refinishing) thickness, replace the rotor. Refer to Brake Rotor Replacement in Disc Brakes.

Is the repair complete?

--

Go to Step 25

--

4

Inspect the following brake caliper assembly components for corrosion:

    • Mounting bolts
    • Sleeves
    • Steering knuckle
    • Brake caliper
    • Brake caliper piston

Refer to Brake Caliper Inspection in Disc Brakes.

Are any of the above components corroded or sticking?

--

Go to Step 5

Go to Step 6

5

Repair or replace calipers. Refer to the appropriate procedure:

    •  Front Brake Caliper Overhaul in Disc Brakes
    •  Rear Brake Caliper Overhaul in Disc Brakes
    •  Brake Caliper Replacement in Disc Brakes

Is the repair complete?

--

Go to Step 25

--

6

Inspect the disc brake pads and brake shoe linings for the following conditions:

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

Do any of the above conditions apply?

--

Go to Step 7

Go to Step 8

7

Replace the brake linings. Refer to the appropriate procedure:

    •  Front Disc Brake Pads Replacement in Disc Brakes
    •  Rear Disc Brake Pads Replacement in Disc Brakes
    •  Brake Shoe Replacement in Drum Brakes

Is the repair complete?

--

Go to Step 25

--

8

Inspect the brake assembly for loose, missing or broken components. Refer to the appropriate procedure:

    •  Front Disc Brake Pads Replacement in Disc Brakes
    •  Rear Disc Brake Pads Replacement in Disc Brakes
    •  Brake Shoe Replacement in Drum Brakes

Are there missing or loose brake assembly components?

--

Go to Step 9

Go to Step 10

9

Tighten or replace loose or missing brake assembly components. Refer to the appropriate procedure:

    •  Front Disc Brake Pads Replacement in Disc Brakes
    •  Rear Disc Brake Pads Replacement in Disc Brakes
    •  Brake Shoe Replacement in Drum Brakes

Is the repair complete?

--

Go to Step 25

--

10

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

Are there brake fluid leaks?

--

Go to Step 11

Go to Step 13

11

  1. Tighten the brake hose or pipe fittings. Refer to Fastener Tightening Specifications .
  2. Start the engine.
  3. Press the brake pedal several times.
  4. Turn OFF the engine.
  5. Inspect the hydraulic brake system for leaks.

Has the leak returned?

--

Go to Step 12

Go to Step 13

12

Replace the brake hose or pipe as necessary. Refer to the appropriate procedure:

    •  Brake Pipe Replacement

Is the repair complete?

--

Go to Step 25

--

13

Inspect the brake caliper piston seal for leaks.

Is the brake caliper piston seal leaking?

--

Go to Step 14

Go to Step 15

14

Replace the brake caliper piston seal. Refer to the appropriate procedure:

    •  Front Brake Caliper Overhaul in Disc Brakes
    •  Rear Brake Caliper Overhaul in Disc Brakes

Is the repair complete?

--

Go to Step 25

--

15

Inspect the park brake for improper adjustment. Refer to Park Brake Cable Service/Adjustment or Parking Brake Shoe Adjustment in Park Brake.

Is the park brake improperly adjusted?

--

Go to Step 16

Go to Step 17

16

Adjust or replace the park brake cable. Refer to the appropriate procedure:

    •  Park Brake Cable Service/Adjustment in Park Brake
    •  Parking Brake Shoe Adjustment in Park Brake
    •  Park Brake Cable Replacement in Park Brake

Is the repair complete?

--

Go to Step 25

--

17

Inspect for an internal leak within the master cylinder. Refer to Master Cylinder Diagnosis .

Is there an internal leak within the master cylinder?

--

Go to Step 18

Go to Step 19

18

Overhaul or replace the master cylinder. Refer to Master Cylinder Overhaul or Master Cylinder Replacement Master Cylinder Replacement in Hydraulic Brakes.

Is the repair complete?

--

Go to Step 25

--

19

Inspect for contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

Is the brake fluid contaminated or improper?

--

Go to Step 20

Go to Step 21

20

Flush the brake system. Refer to Hydraulic Brake System Flushing .

Is the repair complete?

--

Go to Step 25

--

21

Inspect the brake pipes and hoses for a restricted brake fluid passage. Inspect for the following conditions:

    • Low fluid or no fluid output
    • Spurting of fluid while pressing the brake pedal
    • Particles suspended in the fluid

Refer to Hydraulic Brake System Bleeding .

Is there a restricted brake fluid passage?

--

Go to Step 22

Go to Step 23

22

  1. Determine the area of the restriction. This will involve the disassembly of individual brake lines and checking for low or no fluid output
  2. Flush the individual brake line or hose. Refer to Hydraulic Brake System Flushing .
  3. If the restriction cannot be removed, replace the brake line or hose as necessary. Refer to the appropriate procedure:
  4. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .

Is the repair complete?

--

Go to Step 25

--

23

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

Is there air in the brake system?

--

Go to Step 24

Go to Step 25

24

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

Is the repair complete?

--

Go to Step 25

--

25

Verify proper brake system operation.

Does the brake system operate properly?

--

System OK

Go to Hydraulic Brake Diagnostic System Check