Brake Light Failure

[bimmer3214]

WEll thats what the obc says and the check light in the guage cluster and the brake lights work fine checked them light ten million times any one know what it may be

[94BMW325i]

your bulbs are ok? It must be that switch then, my car does that, but recently it hasn't been up on the obc. It's this little switch under your dash I think there is a DIY on this site.

[bimmer3214]

ok thanks i will look for the DYI

[bimmer3214]

well i looked and came up short i found something bout the abs brakes or something but not what i needed anyone else have any suggestions

[WarNox]

mine says it from time to time, i just ignore it now, there must be a bad sensor or something somewhere!

[walke40]

Try 6w bulbs and make sure the holders are clean as just a blip will cause this problem.

[hsenohio]

I had this issue recently. Turns out the sockets for the break lights were worn out and had to be replaced.

[drz]

Check the connections. As said above, you may be looking at new sockets/holders. I know I need to change mine, but I just live with it.

[rfthomas]

I had this very same problem. Replace your bulbs with Sylvania brand bulbs. Apparently they are the OEM. BMWs measure the impedance of the circuits and report discrepancies as failures. I had some Philips brand bulbs in my tail assemblies and replaced them with Sylvania's. It solved the problems!

RFT

[Dudesky_E36]

Originally Posted by rfthomas

BMWs measure the impedance of the circuits and report discrepancies as failures.

This is correct, it measures resistance to current. If it rises above a certain specification, it will read as a dead bulb, even though the lights work. Sometimes just cleaning the socket contacts or bending them out slightly resolves the problem.

[torre 325i]

If it says brake circuit failure, and your brakes work fine and you think that none of the lights are out, then check the wiring harness in the trunk. It's easy, just open your trunk lid and on the left nahd side look where the wires come from the car and up into the trunk lid. Check that they are in good shape and line up well.

I had a brake light circuit fauilure OBC message all the time, but my brake lights worked fine, turns out some of the wires had been bent back and forth enough times that they broke. This can cause all sorts of electrical havoc too. It's worth a look, there are plenty of DIY to fix this problem too.

Cheers