Central locking problem with Ford Focus - any suggestions?

The central locking on our daughter's Fords Focus (63 plate) diesel keeps failing in that the boot locking fails, and the boot lid springs open. We've been back to the dealership twice now, and they keep saying they've fixed it, but they clearly haven't. Any suggestions apart from changing the wiring loom?

Asked on 16 January 2015 by Peter L

Answered by Honest John
Maybe they replaced the solenoid but it's got a wiring fault that completes the circuit. These locks are very vulnerable to interference by moisture.
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