Replace handbrake cable

Check handbrake for faults

In order to determine the cause of the defect, all components of the parking brake should now be checked.

• Raise the vehicle and remove the rear wheels if necessary
• Check handbrake cables for damage and secure fastening

Damage to the dust protection sleeves on the cables was found here (Figure 1).

Release the handbrake cable for further diagnosis

• To do this, remove the rear ashtray cover in the centre console and loosen the adjusting nut of the parking brake until the handbrake lever can be moved slightly

Then check the mobility of the handbrake levers on the rear brake callipers

• Use a screwdriver to slightly deflect the lever in the pulling direction

The handbrake levers and operating levers on both brake callipers move freely and show no visible defects.

Remove parking brake cable

To remove the handbrake cable package, carry out the following work

• Remove the cover from the handbrake lever, i.e. on the centre console
• Loosen the adjusting nut for the handbrake lever until the bolts of the cables move freely
• Unhook fastening bolts
• Remove lower vehicle trims and heat shield
• If necessary, remove the exhaust system from the brackets
• Loosen the mounting plate and brackets on the handbrake cable
• Undo the handbrake cable on the brake callipers and remove the cable

After dismantling, the cause could clearly be attributed to the handbrake cable. The cable could no longer be moved in the Bowden cable. Internal impurities and corrosion have led to an impairment of operating movement (Figure 2).

Check and reset mechanical adjustment devices

Before the new handbrake cable is installed and adjusted, the mechanical adjustment devices in the two brake callipers of the rear axle should first be checked and reset. Correct adjustment of the parking brake is only possible if the parking brake Bowden cables and all moving parts of the parking brake move easily and are functional.

To do this, remove the brake calliper and operate the mechanical lever on the brake calliper until the brake piston extends slightly. After successful testing, turn the piston back completely using a reset tool (Figure 3).

While this task is being carried out, all other components such as brake blocks/pads or guide bolts should be checked for wear and functionality at the same time. Worn or defective components should be replaced.

Put brake callipers back together and reinstall. Then bring the brake pistons into their working position by means of light pedal pumping.

Installing the handbrake cable

Reinstall the new handbrake cable in reverse order.

• Hook the cable to the brake callipers and secure with a fixing plate
• Insert the cable at the top in the handbrake cable holder on the handbrake operating mechanism
• Install and fasten the handbrake cable to the underside in line with the mounting points
• Turn the adjusting nut on the handbrake lever until "no play" tension is achieved or the handbrake levers on the brake calliper lift slightly off the limit stop

Adjusting the handbrake cable - basic setting

• Tighten the handbrake lever to 3-4 detents
• Tighten the adjusting nut until the rear wheels are difficult to turn by hand
• Release handbrake lever
• The rear wheels must now be able to turn freely again. If necessary, turn the adjusting nut back slightly
• Tighten and release the handbrake lever several times using medium manual force
• Operate brake pedal several times with moderate force

The handbrake lever travel should be adjusted in such a way that a blocking of the brake is achieved between 4 - 7 detents.

Check handbrake indicator light

• Set ignition key to ON
• Tighten handbrake lever to detent 1

The indicator lamp should now light up. The wheels must now still turn freely and the rear wheel brakes not drag.

After the basic adjustment, automatic readjustment in the brake callipers of the rear wheel brake means that readjustment of the handbrake is no longer necessary.

Finally check the effectiveness of the handbrake on the brake test stand.