Automobile & Light Truck Certification Test A5 BrakesDrum Brake Diagnosis and RepairMedium
A client reports that their vehicle's parking brake does not hold the vehicle effectively on an incline. A technician inspects the rear drum brakes and finds that the parking brake levers on both sides are seized in the 'off' position. After freeing the levers, what is the NEXT step the technician should take?
- AReplace the brake shoes and drums.
- BAdjust the parking brake cable tension.
- CLubricate the wheel cylinder pistons.
- DBleed the hydraulic brake system.
Show answer & explanationAnswer & explanation
Correct answer: B. Adjust the parking brake cable tension.
After freeing seized parking brake levers, the parking brake cable tension must be adjusted. Seized levers would prevent proper parking brake operation, and after they are freed, the cable slack needs to be taken up to ensure the parking brake engages effectively at the correct lever travel.
Why the other options are wrong
- A. Replacing shoes and drums might be necessary if they are worn, but it's not the immediate next step after freeing seized levers, which directly impacts parking brake function.
- C. Lubricating wheel cylinder pistons is part of a hydraulic brake service, not directly related to mechanical parking brake adjustment.
- D. Bleeding the hydraulic system is unrelated to the mechanical parking brake issue.
Parking Brake Adjustment Post-Repair
After addressing mechanical issues with parking brake components (like seized levers), the parking brake cable tension must be adjusted to ensure proper operation and holding power.
- Ensures effective holding
- Corrects cable slack
- Follows mechanical repair
Memory trick: Fix the parts, then set the tension, then test the retention.