Google indicates the problem with flaky brake lights on R50-R53 is not rare.
cooperSml is pointing in a good direction (water leak makes damage). If the BCM is wet then drying it out may be all that is required for the correction. You would still need to find the leak and get it sealed to prevent recurrence.
This thread with diode failure example is a helpful thread so is worth pursuing. The diode is a low cost part replacement, but working with wire bundles and looks like you have to go into the footwell ....I note that same thread discusses BCM water damage as well... Post #88 has a diode pic
hello all, as i told you, yesterday i've worked in my MINI, i found de BC1 completely dry, and after reconnecting all, my brake lights are still on all time while the key is in :mad2:
so, i wonder if there is something like a reset to do to the BC1 or i'll have to go to the only dealer we have here which aftermarket service is very very bad
I am not sure if notice the tail light and brake light are two different filaments in the same light. The wider filament is the tail light and smaller one is the brake light. At night you can see fairly easy.
When you turn the key at position ignition on and you dont need to start the car
What filament is on in the rear light?
When you step on brakes does the light gets bright? You should see the smaller filament brights up.
Now when you turn you lights on both filaments are on in the rear light?
If your answers are: (ignition on position on)
The smaller filament is on in the rear light
The smaller filament doesnt dim and stay with max light
When turn lights on both filaments are on in the rear light
Then try this:
turn key ignition off
unplug the connector on brake pedal switch
Turn key ignition on
If the brake light is off this time, I will suspect off wrong switch or problem in the connector
yes, i know ther are tali ligths and brake lights in the rear, but i'm sure are brake lights because the third light is on too, i've made that you mentioned, to disconnect the pedal switch, but with the pedal switch connected or disconnected, the lights still ON!!! i mean, whith the key in ON position, brake ligths are on either with or without the pedal switch
I agree with papa-j because is a tedious job and you need to go testing parts sensors, components to be eliminating them. The hardest part of the electrical components in the diagram it is simple easy to see but when installed in the car is a different story. It is not the same thing as the shock, brake pad, the spring, they are right there in front of you. Like I said before I don't know about the diode, but people has dig in before and I found a faulty one it may worth try to find before hand your car to somebody you don't trust.
But if you brake lights are no dimming it can be dangerous too.
