K1 Brake Light on the dash stays on until touching either front or rear brake

[noppo]

There's really only 1 quirk that's been goofy about the K1 i have. The brake light stays on until i hit the front brake (just touching it), or the rear brake (just touching it), and then it will go out.  It's finicky, as sometimes its the front brake, and sometimes its the rear brake that i have to touch. Unpredictable as to which one i will have to touch. It's almost a game to me now, guessing about which one it'll be after the bike starts.

What in the world would be causing this?  Any ideas?

Other facts:

* starts, runs, and handles fine
* the starter needs to be cleaned, as dust in there is causing the bike to not start until i put it in gear and rock it back and forth with the key off, and then it'll start.  This causes the lights to be intermittent at times, which means night riding is not possible until that's fixed
* Everything else works fine - heated grips, lights, flashers, all gages
* ABS works fine

Thoughts?

[Qdude]

I am new to these bikes, but not new to electrical problems.

My k1100lt has a microswitch that works off of the front brake lever. It is under a cover that is held on by two screws. Find it and test it out. If I remember correctly, default brake off position activates the switch. Mine would malfunction if I had its mounting screw too tight. Sounds like that would be a good place to start.

As for the back brake, I have yet to dig in to it. I am going to go out and have a look.

My guess is that there are two different similar issues here, and that they are both caused by brake light actuator adjustments.

[Snowy]

On the K1100 you have to press both brakes to turn the red light off irrspective of order.

[frankenduck]

All K bikes have the same bulb monitor unit and you need to hit both brake switches to make the BMU light go out.

BULB MONITOR UNIT: (a.k.a. "the triangle light")  In the center of the instrument cluster is a red indicator lamp with a triangle.  This light is controlled by a relay of sorts known as the bulb monitor unit, or BMU.  The BMU tests four things:

1) The front brake switch
2) The rear brake switch
3) The tail light running light bulb
4) The brake light bulb

When you first start the bike this light will remain on until you have activated both the front and rear brake switches. If it remains solid after you've applied both brakes then either one of your switches is not working or the tail or brake light bulb is out.  (On ABS equipped bikes, once the brakes have been applied, it will flash in conjunction with the ABS indicator at the bottom of the speedometer faceplate.)

If the BMU light comes on or starts to flicker while you're riding then either your tail or brake light is out or on it's way out.  Note that sometimes you may still have a functioning brake/tail light but either the contacts are getting dirty or the bulb's filament isn't working well enough to make the BMU happy.  Replacing the bulb with a new one should cure this.

[noppo]

What??   What the......??  i don't know what to say.
My affection for the K bike will never end, but this is - just being frankly open and honest - a meaningless feature to me.  Am i the only one who thinks this way?
Why is it this way, when other bikes (to my knowledge) don't do this?
It makes no sense why the BMW engineers would design it that way.
Like i said - quirky.
 :dunno2:

[Snowy]

What??   What the......??  i don't know what to say.
My affection for the K bike will never end, but this is - just being frankly open and honest - a meaningless feature to me.  Am i the only one who thinks this way?
Why is it this way, when other bikes (to my knowledge) don't do this?
It makes no sense why the BMW engineers would design it that way.
Like i said - quirky.
 :dunno2:

I think its a really useful function - lets me know that my brake lights are going to operate when I want them to. Can be really dangerous (to me) if it doesn't work and I'm not aware of it.

[Qdude]

Ha ha,

I thought you were talking about the actual brake light (on the rear of the bike as opposed to the dash light).
When I first got my bike the rear light would "stay on" until I fiddled with "hit" the front brake lever.
I just assumed you had a similar problem.
I tell ya', its hard work making myself look like more of a dumbass.

[jetpoweredmonkey]

I've had the BMU light fail to go off on two occasions, one due to a bad bulb, one due to an intermittent switch.  I think it's a good feature that all bikes should have, but since they don't, it's also a quirky feature that only my K has, and makes me love it more!

[roninvt]

I think it's a good feature that all bikes should have, but since they don't, it's also a quirky feature that only my K has, and makes me love it more!

 :2thumbup:

[TimTyler]

... a meaningless feature to me.  Am i the only one who thinks this way?

Probably.

[noppo]

Then i think i'll probably just have to get used to the idea, as i don't see a way to change it to stop blinking when there is no problem, and blink when there is.  Oh well.  Informative thread it was.

[pdg]

If I've read it all correctly, yours does stop when there is no problem...

It goes out when it has tested everything, and one (well, two) of the things it tests is the operation of the brake light switches - the only way to test a switch is to operate it. That part of it is a one-time test when you start the bike, it then continues to monitor the bulbs (but not the switches) all the time it is on. If it flashes while you're riding then you have a different problem.

Funnily, in recent years cars have started having a system to check the bulbs - having a warning light when a bulb fails. I've not seen anyone say that's a quirky idea or a useless feature :neener:

[noppo]

I thought this thread was over, but guess not. :yow

i'm sure it's useful in some way to some folks, but just not to me.  i just compare it to the GSA, which only barks (to my knowledge) when something's wrong, or other bikes i've owned, or cars that blink this or that if a bulb is out. The notion of forcing the rider to check for something, when there's nothing to check for seems to me to be overkill.  For instance, take the K bikes (only the K bike's??) blinkers speeding up if there's a bulb issue.  That happens if there's an issue.  Otherwise, it doesn't happen.  Which seems to be normal.  Not sure why they didn't use the same logic on the dash brake light on the K bike.  In other words, bark if it's broke, don't if it's not, which i think is the remit (generally speaking) of all dummy light systems on the planet. No?  Seems the engineers at BMW wanted to do something different.  But in my mind, it seems that even luxury cars don't force drivers to check for an issue that doesn't exist.  They let you know when it does.  If my opinion differs from everyone elses, well then, so be it.  No sleep lost for me. We're all in the same K-brotherhood anyway.

So, it's not the end of the world for me. i'll keep the K1 as long as i possibly can regardless of this thing with the brake light. Love the bike, love the history, love riding it, etc.

[Snowy]

I thought this thread was over, but guess not. :yow

i'm sure it's useful in some way to some folks, but just not to me.  i just compare it to the GSA, which only barks (to my knowledge) when something's wrong, or other bikes i've owned, or cars that blink this or that if a bulb is out. The notion of forcing the rider to check for something, when there's nothing to check for seems to me to be overkill.  For instance, take the K bikes (only the K bike's??) blinkers speeding up if there's a bulb issue.  That happens if there's an issue.  Otherwise, it doesn't happen.  Which seems to be normal.  Not sure why they didn't use the same logic on the dash brake light on the K bike.  In other words, bark if it's broke, don't if it's not, which i think is the remit (generally speaking) of all dummy light systems on the planet. No?  Seems the engineers at BMW wanted to do something different.  But in my mind, it seems that even luxury cars don't force drivers to check for an issue that doesn't exist.  They let you know when it does.  If my opinion differs from everyone elses, well then, so be it.  No sleep lost for me. We're all in the same K-brotherhood anyway.

So, it's not the end of the world for me. i'll keep the K1 as long as i possibly can regardless of this thing with the brake light. Love the bike, love the history, love riding it, etc.

I have an '08 GSA and a '94 K1100RS - I understand what you're saying but you're comparing bike technology with essentially 3 decades of design and research between them. I don't find it a problem on the K and in some ways more re-assuring then on the R bike as a simple dab on the brakes turns it off. If I had to rely on one of my bikes taking me around the world reliably it would be the brick not the GSA.

[pdg]

Now, nothing I've said (or am going to say) is meant in an argumentative or derogatory manner - just thought I'd get that in before someone cries as I know I can come across as a little blunt...

You're right in saying that 'other' systems don't expect any testing input from the user, but most don't actually test the switch itself, they only monitor the bulbs. It would be possible for a switch monitoring system to operate differently, say if a double throw instead of single throw switch was used, then it could sense when the switch was being used and inform the user of no output. They just didn't do it that way (and I'd like to think that's) because even with that system say the switch came adrift from it's mount it wouldn't register as a fault, but you'd still have no brake light.

When I did my motorcycle training and tests 17 years ago I was taught a 'pre-ride' checklist that I still use every single time I intend to throw my leg over a bike:

As you walk up to the bike, have a glance around for anything out of place - tyres not flat, not sat in a puddle of oil, brake calipers attached, still got wheels and a petrol tank etc. -- Get on bike, check mirrors (if fitted) are there and adjusted, check stand(s) are retracted fully, check operation of both brakes. -- Start bike, glance at instruments (battery light, oil light etc.) and ride off...

Maybe it's paranoid to do all that (and more, I don't actually think much about it, it's a reflex), but it takes maybe 2-3 seconds over just jumping on and riding away, plus I'm pretty sure I've got a better chance of noticing a fault before I get to the first junction and roll out in front of a bus because a brake hose has burst. To 'adjust' myself to the K system, all I had to do was move the brake check from before turning the key to after...

Oh, and maybe I read it wrong but just because you started a thread doesn't mean a single comment will end it. It's like starting a conversation at a dinner party and expecting everyone to find a new subject if you happen to leave the room :tongue

Ride safe.

[TIV]

The light switch, (probably at the rear) is sticking. Adjust the switch, lubricate it liberally and "voila"...............

[Snowy]

Oh, and maybe I read it wrong but just because you started a thread doesn't mean a single comment will end it. It's like starting a conversation at a dinner party and expecting everyone to find a new subject if you happen to leave the room :tongue

Ride safe.

They still have dinner parties in Salisbury? :lol: :2thumbup:

[pdg]

They still have dinner parties in Salisbury? :lol: :2thumbup:

Of course, the butler arranges them thrice weekly :neener: