Brake Warning Light issues

[xsPain]

On my 85 k100, the brake warning light on the dash flickers on occasionally. Sometimes it will go off on it's own, or I can try the brakes to make it turn off. (Not something I want to do while on the interstate.)

The brakes are due for bleeding, could this be the problem? I looked at the connectors, but they seem okay, and it is not always the same brake that I have to use to get the light off.

Any help?

[roy]

XsPain,
I would say that you have a bad connection some where. Typically lights flickering indicates an intermitant connection.

Good luck, these can be a PITA to find. Hopefully some of the more experienced can give you a better idea of where to start.

[kbasa]

XsPain,
I would say that you have a bad connection some where. Typically lights flickering indicates an intermitant connection.

Good luck, these can be a PITA to find. Hopefully some of the more experienced can give you a better idea of where to start.

It might be worth checking the brake light bulb to make sure it's tight in the socket.

[deilenberger]

On my 85 k100, the brake warning light on the dash flickers on occasionally. Sometimes it will go off on it's own, or I can try the brakes to make it turn off. (Not something I want to do while on the interstate.)

The brakes are due for bleeding, could this be the problem? I looked at the connectors, but they seem okay, and it is not always the same brake that I have to use to get the light off.

Any help?This is usually the brake-warning light module failure mode. BTDT on my '85 - twice.. but worth checking the following before springing for the module:

1. Bulbs - replace all the bulbs in the back with NEW Osram/Sylvania bulbs - with the silver bases. If there are old brass-based bulbs in there - these can cause problems.

2. Brake light switches - you have two.. one on the brake lever up top and one on the rear-brake pedal mount (sideplate) - the one down below is known for failing due to it's location and design. BMW changed designs later to a much better switch - but you're left having to use the same one unless you want to change to later model sideplates and brake pedal. The switch luckily is inexpensive (in BMW terms) - so I'd just replace it. PN is:
61311459569 (see: http://www.realoem.com/bmw/showparts.do?model=0514&mospid=47868&btnr=61_0239&hg=61&fg=25, item 4)

3. Clean the connector for the front brake switch (located in your right grip..) - follow the wire down under the tank to where the connector is. Use some electronic cleaner (or carb cleaner works well) - do in a well ventilated area.

Finally - when none of the above fix the problem - the BMW official diagnostics is - when nothing else fixes it - replace the module.
PN: 61311459003 (http://www.realoem.com/bmw/showparts.do?model=0514&mospid=47868&btnr=61_0237&hg=61&fg=15 - item 17). I wouldn't suggest bothering with a used one. I did that - the used one worked for 6 months and then failed in exactly the same manner as the original one did. A new one lasted as long as I owned the bike.. cost difference was about $15.00 - used one was a false economy.

HTH!