Repair work

WHEN there are signs of problems with the EPB system, it’s worth having it electronically diagnosed by a professional rather than jumping to conclusions. The system is linked by sensors to several other systems around the vehicle (such as the clutch position on manual Discovery models), so an issue could be outside of the EPB system, as well as among the many components within it.

As we saw above, the actuator module gear set can be renewed, and the cables can be renewed individually but, given the labour time for accessing components, plus the fact that all components will have deteriorated, it’s usually best to replace the complete module assembly. If replacing a single failed component, it’s important to confirm that no other parts are defective, otherwise the considerable labour time could be in vain.

Complete replacement is a big job and not something to be attempted without the relevant workshop manual. The electrical system needs to be deactivated before any work (including removal of the brake discs) to prevent the module overrunning and to avoid automatic re-application of the brake.

Access to the module is difficult through the rear wheelarches with the road wheels removed and, mainly, from underneath with the spare wheel removed. Fittings are likely to be corroded and seized. Adjustment and setting of the park brake shoes in relation to the drum can take a couple of hours. Then the new shoes need to be bedded in while driving the vehicle slowly and using the park brake, after first entering a ‘bedding mode’ which temporarily disables the ABS stability functions. The whole operation of setting and bedding the brake shoes is critical, and incorrect settings will eventually cause further damage.