GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2001 🢒 LeSabre 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Park Brake System Diagnosis

Step

Action

Yes

No

DEFINITION: This diagnostic table is designed to diagnose ONLY the components of the PARK brake system in order to determine if the PARK brake system is operating properly. You will be directed by the appropriate Symptom Table to go to other brake system diagnostic tables as appropriate.

1

Were you sent here from a Hydraulic Brake Symptom Table?

Go to Step 4

Go to Step 2

2

Were you sent here from a Park Brake Symptom Table?

Go to Step 4

Go to Step 3

3

Is the symptom related to the ability of the park brake system to hold and/or release?

Go to Diagnostic Starting Point - Park Brake

Go to Diagnostic Starting Point - Hydraulic Brakes

4
  1. Raise and support the vehicle with the rear axle supported by jack stands. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Shift the transmission into NEUTRAL.
  3. With the park brake RELEASED, attempt to rotate the rear wheels to check the rear brakes for a significant amount of drag.

Do the rear brakes have a significant amount of drag?

Go to Step 9

Go to Step 5

5
  1. Shift the transmission into NEUTRAL.
  2. Apply the park brake.
  3. Attempt to rotate the rear wheels to check the rear brakes for a significant amount of drag.

Do the rear brakes have a significant amount of drag?

Go to Step 6

Go to Step 7

6
  1. Release the park brake.
  2. Rotate the rear wheels to check the rear brakes for a significant reduction in the amount of drag.

Did the rear brakes exhibit a significant reduction in the amount of drag?

Go to Step 18

Go to Step 12

7

Visually check the park brake cable connections and the cables that are accessible on the UNDERSIDE of the vehicle for disconnections and/or damage.

Were any or the park brake cables disconnected and/or damaged?

Go to Step 8

Go to Step 9

8

Reconnect or replace the park brake cables as necessary. Refer to the following procedures as necessary:

        (The front park brake cable and the park brake pedal are replaced as an assembly).

Did you complete the repair and/or replacement?

Go to Step 9

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9
  1. Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  2. Have an assistant apply and release the park brake while you observe both of the rear caliper apply levers and the rear park brake cables for free and complete motion during both apply and release.

Did the caliper apply levers and the rear park brake cables exhibit free and complete motion during both apply and release of the park brake?

Go to Step 10

Go to Step 12

10
  1. Cycle the park brake (apply and release) several times to adjust the caliper pistons.
  2. Apply the park brake.
  3. Attempt to rotate the rear wheels to check the rear brakes for a significant amount of drag.

Do the rear brakes have a significant amount of drag?

Go to Step 11

Go to Step 12

11
  1. Release the park brake.
  2. Rotate the rear wheels to check the rear brakes for a significant reduction in the amount of drag.

Did the rear brakes exhibit a significant reduction in the amount of drag?

Go to Step 18

Go to Step 12

12
  1. Disconnect the intermediate park brake cable from the front cable. Refer to Parking Brake Intermediate Cable Replacement .
  2. Disconnect the rear park brake cables from the caliper apply levers. Refer to Parking Brake Rear Cable Replacement .
  3. Check the intermediate and rear park brake cables for free movement.
  4. Using a wrench on each of the caliper piston apply lever bolts, apply and release the levers; observe for a free return of the levers when released.

Do any of the park brake cables checked require replacement?

Go to Step 14

Go to Step 13

13

Did the brake caliper apply levers return freely when released?

Go to Step 20

Go to Step 19

14

Replace any of the park brake cables checked that do not have free movement. Refer to Parking Brake Intermediate Cable Replacement and/or Parking Brake Rear Cable Replacement .

Did you complete the replacement?

Go to Step 15

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15
  1. Cycle the park brake (apply and release) several times to adjust the caliper pistons.
  2. Apply the park brake.
  3. Attempt to rotate the rear wheels to check the rear brakes for a significant amount of drag.

Do the rear brakes have a significant amount of drag?

Go to Step 16

Go to Step 17

16
  1. Release the park brake.
  2. Rotate the rear wheels to check the rear brakes for a significant reduction in the amount of drag.

Did the rear brakes exhibit a significant reduction in the amount of drag?

Go to Step 18

Go to Step 17

17
  1. Disconnect the intermediate park brake cable from the front cable. Refer to Parking Brake Intermediate Cable Replacement .
  2. Disconnect the rear park brake cables from the caliper apply levers. Refer to Parking Brake Rear Cable Replacement .
  3. Using a wrench on the caliper piston apply lever bolt, cycle each caliper piston (apply and release) several times to adjust the caliper pistons.
  4. Have an assistant use a wrench on the caliper piston apply lever bolt to apply and maintain the caliper piston.
  5. Attempt to rotate the rear wheels to check the rear brakes for a significant amount of drag.
  6. Repeat steps 4 and 5 for the other side of the vehicle.
  7. Release the caliper piston apply levers.
  8. Rotate the rear wheels to check the rear brakes for a significant reduction of drag.

Did the brake calipers apply and release properly?

Go to Step 18

Go to Step 19

18
  1. Grasp the intermediate park brake cable and pull downward to check the amount of tension on the park brake cables.

    2. The park brake cables should have a moderate amount of tension.

  2. Quickly release the intermediate cable and observe for a quick and complete return of the cable.

Did the park brake cables have a moderate amount of tension and exhibit a quick and complete return?

Go to Step 21

Go to Step 20

19

Replace the appropriate rear brake caliper(s). Refer to Rear Brake Caliper Replacement in Disc Brakes.

Did you complete the replacement?

Go to Step 21

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20

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

Did you complete the replacement?

Go to Step 21

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21
  1. With the transmission still in NEUTRAL, apply the park brake.
  2. Attempt to rotate the rear wheels to check the rear brakes for a significant amount of drag.
  3. Release the park brake.
  4. Rotate the rear wheels to check the rear brakes for a significant reduction of drag.

Did the park brake apply and release properly?

Go to Step 22

Go to Step 4

22

Install or connect any components that were removed or disconnected during diagnosis.

Is the operation complete?

Park Brake System OK

Return to Symptom Table

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