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Diagnostic Starting Point - Park Brake

Begin the system diagnosis by reviewing the system description and operation. Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Park Brake in order to identify the correct procedure for diagnosing the system and where the procedure is located.

Symptoms - Park Brake

Important: Review the system operation in order to familiarize yourself with the system functions.

Refer to Park Brake System Description and Operation .

Visual/Physical Inspection
    • Inspect for aftermarket devices which could affect the operation of the park brake system.
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnosis the symptom:

Refer to Park Brake Will Not Hold or Park Brake Will Not Release .

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 .
  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 19

Go to Step 6

6

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

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

Go to Step 7

Go to Step 8

7

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

Did you complete the repair and/or replacement?

Go to Step 19

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8

Check the adjustment of the park brake and adjust if necessary. Refer to Park Brake Adjustment .

Was the park brake adjusted properly?

Go to Step 19

Go to Step 9

9

Notice: Do not depress the brake pedal with the brake rotors and/or the brake drums removed, or with the brake calipers repositioned away from the brake rotors, or damage to the brake system may result.

  1. Remove the rear brake rotors. Refer to Rear Brake Rotor Replacement .
  2. Inspect the park brake shoe hardware for looseness, damaged, broken or missing components.
  3. Check the park brake actuators for a seized condition.

Does the park brake hardware and/or the park brake actuators require replacement?

Go to Step 10

Go to Step 11

10
  1. Replace park brake hardware components as necessary. Refer to Parking Brake Shoe Replacement .
  2. Replace the park brake actuators as necessary. Refer to Parking Brake Actuator Replacement .

Did you complete the replacement?

Go to Step 19

--

11

With the aid of an assistant, apply and release the parking brake while observing the cables for free movement

Do the park brake cables move freely?

Go to Step 12

Go to Step 14

12

Check the adjustment of the park brake. Refer to Park Brake Adjustment .

Was the park brake adjusted properly?

Go to Step 19

Go to Step 13

13
  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 19

Go to Symptoms - Park Brake

14

Disconnect the park brake cable connections that are accessible on the UNDERSIDE of the vehicle one at a time and check each cable for free movement.

Do any of the park brake cables accessible on the underside of the vehicle require replacement?

Go to Step 15

Go to Step 16

15

Replace any of the park brake cables that do not have free movement - not releasing properly. Refer to the following procedures as necessary:

Did you complete the replacement?

Go to Step 19

--

16

Inspect the park brake lever for proper operation and replace if necessary. Refer to Parking Brake Lever Pedal Assembly Replacement .

Did you find and correct the condition?

Go to Step 19

Go to Step 17

17

Check the adjustment of the park brake. Refer to Park Brake Adjustment .

Did you find and correct the condition?

Go to Step 19

Go to Step 18

18
  1. Replace the component that is used to adjust the park brake system. Refer to Parking Brake Lever Pedal Assembly Replacement .
  2. Adjust the park brake. Refer to Park Brake Adjustment .

Did you complete the replacement and adjustment?

Go to Step 19

Go to Symptoms - Park Brake

19

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

Did you complete the operation?

Park Brake System OK

Go to Symptoms - Park Brake

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