SPECIFICATIONS

Torque Specifications

DESCRIPTION AND OPERATION

Parking Brake

The parking brake system consists of the following components:

• Parking brake control and front cable assembly
• Rear parking brake cables

The parking brake system is a mechanical system that activates a self-adjusting brake ratchet system within the rear brake caliper.

The parking brake system is cable-actuated and controlled by an independent foot-operated parking brake control. The parking brake system is actuated when the parking brake control is pressed and released by pressing the parking brake control a second time. The parking brake control applies tension to rear parking brake shoes through the front parking brake cable and conduit, and the LH and RH rear parking brake cables. The respective rear parking brake assemblies are then applied.

The parking brake cable tension is self-adjusting inside the parking brake control.

DIAGNOSIS AND TESTING

Parking Brake

Principles of Operation

Parking Brake System

The parking brake actuator is a spring-loaded, self-adjusting, foot-operated control. When the parking brake control is pressed once, tension is applied to the front parking brake cable. Pressing the pedal a second time releases the tension. This tension pulls on the RH rear parking brake cable. At the same time, the tension in the front cable causes the RH cable conduit to attempt to straighten out, causing tension that pulls the LH rear cable. Both cables are attached to their respective rear parking brake levers, applying the rear brake calipers. These levers actuate a mechanical corkscrew device inside the caliper piston. When the parking brake cable pulls on the lever, this corkscrew device pushes the piston against the pads. Normal brake pad wear allows the caliper piston to move outward from the caliper housing. This action maintains proper park brake adjustment.

Inspection and Verification

Check the operation of the parking brake system with the vehicle on a hoist and the parking brake control fully released. Check for any damaged cables and install new components as necessary.

The first indication that something may be wrong in the parking brake system is a change in the feeling through the parking brake control. The parking brake not holding on an incline or dragging after being released are also indicators of system concerns.

1. Verify the customer concern.

2. Visually inspect for obvious signs of mechanical damage.

Visual Inspection Chart

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

4. If the cause is not visually evident, verify the symptom and GO to Symptom Chart.

Symptom Chart

Pinpoint Tests

Pinpoint Test A: The Parking Brake Does Not Apply/Hold Vehicle

Normal Operation

When the parking brake control pedal is pressed, the pedal should move a short distance, with more pressure needed to apply the pedal as it gets closer to the floor, until the parking brake is fully applied. When the parking brake control is pressed, tension is applied to the front parking brake cable. This tension pulls on the RH rear parking brake cable, which is attached to the RH rear parking brake actuator, and applies the RH rear brake caliper. At the same time, the tension in the front cable causes the RH cable conduit to attempt to straighten out. This straightening effect causes tension that pulls the LH rear cable, which is attached to the LH rear parking brake actuator, and applies the LH rear brake caliper.

This pinpoint test is intended to diagnose the following:
• Front parking brake cable and conduit
• Parking brake control
• Rear parking brake cables and conduits
• Rear brake calipers

PINPOINT TEST A: THE PARKING BRAKE DOES NOT APPLY/HOLD VEHICLE

Pinpoint Test B: The Parking Brake Will Not Release

Normal Operation

When the parking brake control is fully applied and the pedal is pressed a second time, the ratchet mechanism in the parking brake control releases the tension on the parking brake cables and conduits. The springs on both rear brake calipers provide the force necessary to return the brake pads and cables to their released position.

This pinpoint test is intended to diagnose the following:
• Front parking brake cable and conduit
• Parking brake control
• Rear parking brake cable and conduit
• Rear brake calipers

PINPOINT TEST B: THE PARKING BRAKE WILL NOT RELEASE

GENERAL PROCEDURES

Parking Brake Cable Tension Release

1. With an assistant, release the parking brake cable tension by pulling down on the front cable at the cable-to-cable union until the parking brake control sector rotates to its stop and a 4 mm (0.15 in) x 150 mm (5.9 in) retainer pin can be inserted.

2. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to Section 100-02.

3. NOTE: Make sure that the cable-to-cable union is connected to the front and rear cable before removing the brake control retaining pin and that the cable tension is reloaded slowly.

   Disconnect the cable at the cable-to-cable union by releasing the locking tab.

REMOVAL AND INSTALLATION

Parking Brake - Exploded View

1. For additional information, refer to the procedures in this section.

Parking Brake Cable - Rear

Removal and Installation

Both cables

1. Release the parking brake cable tension. For additional information, refer to Parking Brake Cable Tension Release in this section.

RH cable

2. Separate the RH cable from the LH at the conduit equalizer and remove the cable from the wireform bracket.

3. Remove the 3 parking brake cable bracket bolts.
   • To install, tighten to 15 Nm (133 lb-in).

4. Remove the RH wheel well bracket bolt.
   • To install, tighten to 23 Nm (17 lb-ft).

LH cable

5. Disconnect the conduit equalizer from the RH cable at the equalizer.

6. Remove the wireform bracket bolt and separate the LH cable and bracket from the RH cable.
   • To install, tighten bolt to 12 Nm (106 lb-in).

7. Remove the LH wheel well bracket bolt.
   • To install, tighten to 23 Nm (17 lb-ft).

Both cables

8. Release the parking brake cable from the brake caliper and remove the cable.

9. To install, reverse the removal procedure.
   • Inspect the parking brake system for correct operation.

Parking Brake Control

Removal and Installation

1. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to Section 100-02.

2. Release the tension on the parking brake cable. For additional information, refer to Parking Brake Cable Tension Release in this section.

3. Remove the Smart Junction Box (SJB) and bracket. For additional information, refer to Section 419-10.

4. Remove the scuff plate trim panel and the lower cowl side trim panel. For additional information, refer to Section 501-05.

5. Disconnect the parking brake switch electrical connector.

6. Remove the parking brake control nut.
   • To install, tighten to 30 Nm (22 lb-ft).

7. Remove the 2 parking brake control bolts.
   • To install, tighten to 30 Nm (22 lb-ft).

8. Position the carpet aside and position the cable conduit grommet through the floor.

9. Remove the parking brake control and front cable assembly.

10. To install, reverse the removal procedure.
    • Inspect the parking brake system for correct operation.