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Discussion Starter #1
Hi all, I've had this problem for about a week, the brake lights come on as soon as the ignition is turned on (to position II and beyond). Changed all rear bulbs (no scorch marks on contacts or brittle plastic), checked the loom from boot lid to boot and it seems fine and I have also changed the brake light switch - twice! Is there a bad batch of switches around or does the LCM ever produce this fault. Many thanks.
 

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Whenever I had this problem with my Ford Focus a few years ago it was always the pedal switch. As you have suggested you may have been unlucky and got two dud ones.
 

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It has been known for the LCM to have shorted switching transistors for the headlamps which stay on continuously. Could be a similar problem for the rear brake lights as well since you have done all your other checks. The feed from the brake light switch goes to the LCM and then to the lights.
 

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Discussion Starter #4
All fixed. Contacted very helpful LCM Repairer who thought LCM failure unlikely and to check wiring. One of the dozens of connections must have been loose and remaking all the joints from light switch to LCM has fixed the fault.
 

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Discussion Starter #5
Pretty hacked of with this now! Car is back, all three brake lights permanently on when ignition is on plus "helpful" reminder on dash that there is a problem with the brake light bulbs!
The car has done virtually no mileage since I thought I'd fixed it months ago, so with several new brake light switch replacements, continuity to LCM OK and earths all checked I've ran out of ideas.
Surely this isn't an isolated symptom of a dodgy ignition switch?

Help gratefully accepted!
 
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