Parking brake repair is a somewhat rare, but very necessary aspect of brake maintenance. The parking brake is a critical safety item, and any do-it-yourself mechanic should take the time to make sure their own brake works properly.
Replacing a parking brake isn't difficult, but it is important to know that some typical parking brake problems are the result of normal vehicle use. For instance, a parking brake that doesn't seem to grip with enough force may be in need of adjustment.Most cars to have a specification as to how high the brake should be when it is applied.
Adjustments are necessary because parking brake cables have a tendency to stretch as they age. Adjustment procedures vary quite a bit, so it may be a good idea to consult a service manual from Chilton, Haynes or Bentley Publishers. The adjustment process works by removing the excess slack in the parking brake wire, allowing the rear brakes to be applied with the amount of pressure intended by the manufacturer.
Another common issue associated with parking brakes is a component that sticks (or stays engaged) when the lever inside the car is released. This problem is often due to a lack of lubrication. If you experience a sticking brake, it may be a good idea to grease the sliding mechanisms and actuator levers on the rear brake calipers. This will often fix a sticky component, but in other instances it may be necessary to disassemble the rear brakes before the cause becomes clear.
Replacing a broken cable is a good project for an amateur mechanic. The first step is to remove the rear (in the case of some Saab vehicles the parking brake is located on the front) wheels to gain access to the brake assembly.
When the brakes are exposed, the end of the brake cable should be within easy reach. At this point any mounting hardware can be removed, and the cable can be freed from the caliper. Once this has been accomplished, the process is as simple as following the cable (and removing any more points of attachment) to the interior of the vehicle.
Once you have traced the cable to its point of entry into the car, some minor interior trim disassembly may be needed to gain access to the underside of the parking brake handle. When this is finished, the interior portion of the cable can be undone and the cable is free to be pulled out from underneath the car. The new cable can then be attached to the parking brake handle and tensioned for proper engagement.
Some new vehicles feature electric parking brakes. These brakes work in the same fashion as cable-operated systems, but use electric motors instead of physical effort to apply the brake. Electric parking brakes may require use of a factory scan tool to place them into a service mode before repairs are made. Backyard mechanics may find this frustrating, as performing a rear brake job is impossible without first electronically releasing the brakes.
A properly maintained parking brake will not only help your car pass required safety inspections, but will allow you (and your neighbors) to sleep soundly knowing your car is in no danger of rolling down a steep hill.