Diagnosis and Testing Inspection and Verification - Verify the customer concern by operating the parking brake system.
- Visually inspect for obvious signs of mechanical or electrical damage.
Visual Inspection Chart Mechanical | Electrical | - Parking brake control.
REFER to: Parking Brake Control (206-05 Parking Brake and Actuation, Removal and Installation). - Cable and conduit.
REFER to: Parking Brake Rear Cables (206-05 Parking Brake and Actuation, Removal and Installation). | - Parking brake warning circuit.
REFER to: Instrument Cluster (413-01 Instrument Cluster, Diagnosis and Testing). | - If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
- If the concern is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart Symptom | Possible Sources | Action | The parking brake will not apply | * Parking brake control. * Cable and conduit. | * | The parking brake will not release | * Parking brake control. * Cable and conduit. | * | Pinpoint Tests PINPOINT TEST A : THE PARKING BRAKE WILL NOT APPLY | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | A1: CHECK FOR MISADJUSTED REAR PARKING BRAKE CABLE | | 1 Operate the service brake pedal several times to take up any wear clearance at the rear brake pads. | | Does the parking brake now engage correctly? Yes Vehicle OK No Check for correct clearance at the parking brake caliper levers. REFER to: Parking Brake Cable Adjustment (206-05 Parking Brake and Actuation, General Procedures). GO to A2. | A2: CHECK FOR WORN REAR BRAKE PADS | | 1 Inspect the rear brake pads for excessive wear. REFER to: Specifications (206-04 Rear Disc Brake, Specifications). | | Are the rear brake pads OK? Yes No INSTALL new rear brake pads. REFER to: Brake Pads (206-04 Rear Disc Brake, Removal and Installation). TEST the system for normal operation. | A3: CHECK FOR DAMAGED PARKING BRAKE CABLES | | 1 Inspect the parking brake cables and conduits for damage, rust or fraying. | | Are the parking brake cables and conduits OK? Yes CHECK for other causes such as loose parking brake control or conventional brake system components. No REPAIR or INSTALL cables and conduit as necessary. REFER to: (206-05 Parking Brake and Actuation) Parking Brake Rear Cables (Removal and Installation), Parking Brake Cable Adjustment (General Procedures). TEST the system for normal operation. | PINPOINT TEST B : THE PARKING BRAKE WILL NOT RELEASE | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | B1: CHECK PARKING BRAKE SYSTEM | | 1 Raise and support the vehicle on a lift with the parking brake fully applied. REFER to: Lifting (100-02 Jacking and Lifting, Description and Operation). - With the aid of another technician, release the parking brake and check the operation of the brake cables and levers.
| | Did the parking brake release? Yes CHECK the other causes such as conventional brake system components. REPAIR or INSTALL new components as necessary. No | B2: CHECK PARKING BRAKE LEVER | | 1 With the aid of another technician loosen the parking brake cable tension at the parking brake adjustment nut and observe the parking brake caliper lever, one at a time. - Check if the rear wheels turn freely or if the parking brake caliper levers moved to the OFF position.
| | Did the rear wheels turn freely? Yes INSTALL a new parking brake control. REFER to: Parking Brake Control (206-05 Parking Brake and Actuation, Removal and Installation). TEST the system for normal operation. REFER to: Parking Brake Cable Adjustment (206-05 Parking Brake and Actuation, General Procedures). No | B3: CHECK REAR PARKING BRAKE CABLES | | 1 Disconnect the parking brake rear cable at the rear brakes, one at a time. - Loosen the parking brake cable tension at the parking brake cable adjustment nut.
- Pull the parking brake rear cable rearwards at the parking brake caliper lever and check if the cable moved freely.
- Rotate the wheel affected by the disconnected parking brake.
| | Did the parking brake rear cable move freely? Yes INSTALL a new caliper housing assembly. REFER to: Brake Caliper (206-04 Rear Disc Brake, Removal and Installation), Parking Brake Cable Adjustment (206-05 Parking Brake and Actuation, General Procedures). TEST the system for normal operation. No REFER to: (206-05 Parking Brake and Actuation) Parking Brake Rear Cables (Removal and Installation), Parking Brake Cable Adjustment (General Procedures). | |