Brake light permanently on - have done search but got other q's - thanks

I've done a search so I appreciate this is not a new topic. Having read the various threads on page 1 of search, I still have a few questions which I'm hoping someone can help with please.

The bike is a 2005 1150GSA with 40k miles on the clock. The brakes have ABS and servo assist. (It's the ABS and servo bits prompting my additional questions.)

The bike is used for commuting 60 miles 3 days a week, almost all of it on dual carriageway.

The red light warning triangle popped on about two weeks ago. From reading other threads and sources, on Sunday just gone I checked the tail bulb and it was fine but I replaced it anyway. The next day I noticed that the red warning triangle came on and stayed on as soon as I used the rear brake and when I got to work I further noticed that the brake light was on full blast.

I've had a look at the both front and rear contact switches and they appear in good order - no corrosion or bending of the contact strips. The hand guard is not interfering with the front lever either.

I could only trace the rear cable to a plug which once disconnected also disabled the ABS and servo.

Sooooo, the only thing that's been changed is the tail bulb but I'm having difficulty believing that could be the problem. I also need to change my rear pads but again I cannot believe that worn pads would cause this issue.

Am I missing something obvious? A dodgy earth maybe?

Also, is it possible to disconnect the brake light switch without interfering with the ABS and servo?

Thanks,

Cam

Have you checked out this thread ..... http://ukgser.com/forums/showthread.php/190484-abs-red-warning-triangle-light-staying-on-1150-GS

Is your bulb located correctly, the right way round; seemingly the system anticipates the incandescent bulb loads & triggers the warning if not seen.

Otherwise I am thinking a wiring fault or your rear brake-light switch (not sure which type you have on such a late 1150). Does the rear brake pedal return freely? Have you adjusted the pedal height?

Back in August 2016 I had a problem with my brake light flickering all the time (annoyed the hell out of anybody following), then the light stopped working and the the dash warning lights came on. Did all the usual checks with no success, including changing the bulb as you have done. Still no joy, then Tadgh and Dr Farkoff suggested checking out the bulb contacts in the socket; scroll back 2 years....

"Quick trip into the garage tonight and pulled the new bulb. Bulb OK but looked into the socket and saw there was some black contamination on the contacts - looked like the arcing deposits you used to get on the contact breakers back in the days when I still had hair. Scraped it all clean with a flat scalpel, put the bulb back in and everything now works as it should. Then took the precaution of removing the bulb and applying ACF 50 to the contacts and the bulb!"

2 years on and everything is still working fine; could be worth checking the contacts in your socket, you migh get lucky.

squibb34 said:

Have you checked out this thread ..... http://ukgser.com/forums/showthread.php/190484-abs-red-warning-triangle-light-staying-on-1150-GS

Is your bulb located correctly, the right way round; seemingly the system anticipates the incandescent bulb loads & triggers the warning if not seen.

Otherwise I am thinking a wiring fault or your rear brake-light switch (not sure which type you have on such a late 1150). Does the rear brake pedal return freely? Have you adjusted the pedal height?

Click to expand...

Squibb - thanks, I hadn't seen that thread you posted. TBH, I hadn't appreciated that the red warning triangle was linked to the ABS/braking system in the first place. On that note, I wasn't aware that the bulb could be loaded incorrectly either. I shall check tonight and report back.

I'm really hoping it's not a wiring fault, tracing broken wires and dodgy earths are not my strong point.

Mac Henderson said:

Back in August 2016 I had a problem with my brake light flickering all the time (annoyed the hell out of anybody following), then the light stopped working and the the dash warning lights came on. Did all the usual checks with no success, including changing the bulb as you have done. Still no joy, then Tadgh and Dr Farkoff suggested checking out the bulb contacts in the socket; scroll back 2 years....

"Quick trip into the garage tonight and pulled the new bulb. Bulb OK but looked into the socket and saw there was some black contamination on the contacts - looked like the arcing deposits you used to get on the contact breakers back in the days when I still had hair. Scraped it all clean with a flat scalpel, put the bulb back in and everything now works as it should. Then took the precaution of removing the bulb and applying ACF 50 to the contacts and the bulb!"

2 years on and everything is still working fine; could be worth checking the contacts in your socket, you migh get lucky.

Click to expand...

Mac - thanks for your advice, haven't checked the contacts on the bike for the rear bulb but I'll have a wee look later.


Tried swapping to a new bulb last night and still had the issue. What I did notice was that the one filament (presumably the brake light filament) is dulled until you press/pull on the brake and then it brightens to match the full illumination of the other (presumably running light filament).

On this basis, I would have thought it suggests a problem with the running light and not the braking system though the red warning triangle is still illuminated too.

Sounds like you have a broken/corroded wire in the tail lamp assembly they are well know for corroding

The brake filament being dim and then brightening is a safety feature of the Integral ABS where if it does not "see" a connection between certain vaules at the tail lamp it will feed a lower current to the brake lamp to provide you with a visible tail lamp

I suggest that you investigate wiring / connections / bulb holder assembly at the tail lamp and where teh cables pass up into the frame area to the front

You want to see 12 v and above at the wire that is grey with a black trace at or near the tail lamp with ignition on and nothing through the brake +ve (brown is negative or earth)

Beancounter said:

Tried swapping to a new bulb last night and still had the issue. What I did notice was that the one filament (presumably the brake light filament) is dulled until you press/pull on the brake and then it brightens to match the full illumination of the other (presumably running light filament).

On this basis, I would have thought it suggests a problem with the running light and not the braking system though the red warning triangle is still illuminated too.

Click to expand...

Finally found some time to have another poke around... problem still exists with the tail light staying on fully.

What I've tried so far:

* new bulbs;
* cleaned the bulb socket and connectors - no corroded wires evident;
* both brake switches working correctly;
* despite switches on good order, I'm getting 12v through to tail light and brake light even when brakes not applied;
* tried 're-setting' the ABS system by grounding the wire in pin 2, switching the ignition on, holding the ABS button for 8 seconds and switching ignition off;
* brake fluid level is high enough to not trigger a warning;

I'm at a loss now and am thinkin of taking it to a professional to look at. I'm based in the Medway towns, can anyone recommend a mechanic for me to speak to? Happy to travel a reasonable distance. Thanks.

Beancounter said:

Finally found some time to have another poke around... problem still exists with the tail light staying on fully.

What I've tried so far:

* new bulbs;
* cleaned the bulb socket and connectors - no corroded wires evident;
* both brake switches working correctly;
* despite switches on good order, I'm getting 12v through to tail light and brake light even when brakes not applied;
* tried 're-setting' the ABS system by grounding the wire in pin 2, switching the ignition on, holding the ABS button for 8 seconds and switching ignition off;
* brake fluid level is high enough to not trigger a warning;

I'm at a loss now and am thinkin of taking it to a professional to look at. I'm based in the Medway towns, can anyone recommend a mechanic for me to speak to? Happy to travel a reasonable distance. Thanks.

Click to expand...

I've got the exact same intermittent problem with mine, with the warning/tail lamp. Tried a few bulbs, tore the holder out and cleaned all the contacts, and it still came on intermittently. I only had the problem with the brake light being stuck on when I stupidly put the bulb in upside down. I have no idea if it's just mine but the actual bulb mount is plastic and is a pile of garbage, it seems pretty hard with some of the bulbs I have to actually mount it properly without it wobbling loose.

Would be interested to hear what it is. I even ordered the LED replacement from motorworks which was apparently compatible with iABS but I get the warning light immediately with that every single bloody time, whereas with the bulb at least it was random. Whoever owned my bike last has wired so much unnecessary shite in mine, it's going to be a right job figuring out what's causing it.

I only live down the road, I don't know anyone really close by but you have Steptoe round Kingston way. BGM is based near Pembury and you have Mark Holden in Bromley (MH Motorcycles?). Haven't used BGM/MH but I've heard good things.

Just an idea - has the right hand guard moved slightly so the front brake isn't completely off ? I had the rear light / warning triangle issue day of the MOT. Pushed the hand guard down about 2mm and all was well.
Best of luck
Dave

If I recall correctly, you need to make a connection to turn off the light. If you've a broken wire somewhere, it will stay on. The first thing I'd do is bypass the brake switches. Plug them out and bridge the connection with a bit of wire.

Do you have a multimeter or some other reliable way of checking the wiring? There could be a break inside the insulation somewhere.

Is the servo initialising normally and functioning okay?

EDIT: The logic for turning on and off the brake lights is performed by the electronics in the servo, so if you don't find a break in a wire or something, I'd be wary of the servo. I don't trust those servos. Mine failed at low speed on a quiet back road, but it just as easily could have been at high speed. Mine also behaved a little odd from time to time for a few weeks before it failed.