Hello Paul, my handbrake does not hold well anymore, especially when I park on a slope. A friend told me the cable might be stretched or worn out. How does the hand brake cable work, and what risks do I face if it fails? Can it be adjusted or only replaced? Steven
Hello Steven, it is quite unnerving as well as risky to park on a slope with a bad handbrake or parking brake. To understand how the handbrake works, it is useful to appreciate its importance. The car’s handbrake is a mechanical system that works independently of the hydraulic foot brake system. Older handbrake designs use a hand lever or foot pedal, while newer designs with electronic parking brakes (EPB) use a button. All handbrake systems will mechanically or electronically (EPB) operate a cable, which is connected to the rear brakes.
When you pull the steel cable or set of cables, this pulls a lever or mechanism which engages the rear brake pads or shoes against the rear disc rotors or drums, depending on the rear brake design. Briefly described, pulling the handbrake lever, kicking the parking foot brake pedal or pressing the parking brake button will tension a cable, which will apply the rear brakes to secure the rear wheels and your vehicle. Although handbrake systems are intended to securely hold the rear wheels when you park, there are a couple of serious risks you face if they fail. The handbrake helps you secure the vehicle after you park.
This is most important when you park on an incline where there is a risk of the car rolling away or downhill and causing severe injury to occupants or other road users and property damage. The handbrake or parking brake helps you during hill starts, where your car does not have the anti-roll back feature. This is crucial for avoiding rolling backwards when you are in situations such as a traffic jam on a hilly road. There is also a risk of damaging the transmission if you park on a slope, have a faulty hand (parking) brake and leave the car in gear one (manual) or Parking (automatic). This would put a strain on the gearbox and reduce its lifespan over time.
On very rare occasions, the main hydraulic brakes could fail, and you need to resort to the handbrake or parking brake as a last resort to stop the vehicle. If you have neglected repairing the faulty handbrake, you will not be able to use it as a brake of last resort, when the primary hydraulic brake system fails. Your car’s handbrake or parking brake will need urgent attention to prevent the above risks. Sometimes the handbrake or parking brake system needs adjustment to make it work better.
Over time, the cables that pull the mechanical levers tend to slacken. Using recommended know-how and tools, the cables can be adjusted by a mechanic to create enough tension to apply the hand or parking brake promptly and securely. In cases where the cables are frayed or broken, mechanical components such as the levers, springs or handbrake shoes have failed, they can be replaced to restore normal operation. Below are pictures of worn-out handbrake components.