Brake light on

[Kavadarci]

Hi,
I bought the car with the brake lining and brake light on.
Brake lining was fixed with new rotors pads and sensors but brake light continues to come on.

I've cleaned the contacts and check the bulbs.
Every light works fine.
I replaced the brake light switch (which worked fine) with a new one and same result.
What might be causing this light to come on?

I do have an issue with the rpm gauge and temperature not working and i suspect some wiring in the dash. Could that be it?
Thank you.

[Vincenze]

When you start the car, the brake light is always on until you press on the brake pedal.

The light is controlled by the black box near the antenna and audio amplifier.
It has reed switches with enameled wires wrapped around them. When enough current flows through an enameled wire, it creates a magnetic field, and the reed switch inside of it deactivates.

If somebody installed LED lights, the current is low.

The picture is not mine.



This may help https://e30journey.blogspot.com/2017...ake-light.html

[Kavadarci]

Ok
i don’t have this box. Where is it exactly?

[Vincenze]

It's over the audio amplifier in the trunk.

If you don't have an amplifier, I don't know where it can be.

[Kavadarci]

Definitely not there
does it matter if convertible?

[Kavadarci]

Found it
it's behind rear driver side panel
it does get 12v and all looks good
same with the third stop light mall cleaned and measures ok

What else to check?

[Vincenze]

You should check the behavior of the brake light reed relay by checking its resistance.
I believe it should be disconnected when the brake lights are off, and it should be connected when the brake lights are on. Or vice versa.

The next obvious place to check is the instrument cluster. Change the batteries if you haven't done so. Check soldering connections using a loupe.

[Kavadarci]

Ok,
I’ve check the relay and it is as expected.
i cleaned every connector even removed the plastic back of the tail lights.
i tried different bulbs and the light is still there.
unless I’ve missed something I really start to believe it is something with the dash cluster.
i don’t have the rpm gauge and temperature working and sometimes on a bump the brake lining light shows up.
light hit on the dash and it goes away.

does the dash problem have something to do with the brake light problem I have? Wondering what is the connection.
i do plan to take it out and fix it.