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Q: Brake lights on constantly

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Hi I am having a frustrating problem with my Mazda 3. The brake lights stay on constantly when there is power to the battery. But when I pull the room fuse from under the bonnet they work as normal, however doing this stops anything from working on the inside of the car. I have changed the sensor on the wheel bearings/hubs, I have replaced the brake switch under the pedals. Replaced all the fuses both outside and inside, replaced the brake lights completely. What could this be? I am totally baffled

My car has 120000 miles.
My car has a manual transmission.

Hi there:

It’s quite possible that you have a faulty electrical relay from the fuse box to the brake lights that is supplying power to illuminate the light at all times. It’s also possible that a brake sensor on top of the pedal is stuck in the open position due to a faulty ground. The best advice I can offer is to have a professional mobile mechanic come to your location and complete an electrical problems inspection; so they can help you pinpoint the source of this issue and recommend the right repairs be completed.

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