Brake Servo & Speedo Problem

[piebaps]

Hi all. Any ideas? Here's the problem.

Riding along at normal road speed when brake failure warning light (red triangle/fast flash) comes on and speedo stops working. Stop the bike on the kill switch and the brake servo motor is clearly audible.

No obstructions on hand guard or foot pedal and no brake lights on.

Switch off on key and switch back on again (allowing the full start up sequence of course) and all is well again...........at least for a short while until without warning, it happens again.

Latest is the fault now appears to be permanent with residual braking only.

Anyone had this kinda stuff before, so I can give the dealer a helping hand on Monday. Bike is 2005 and still under warranty so they will be fixing it at their own expense happily.

 

[TRICKY1200]

Hi piebaps it sound like rear abs sensor in final drive not working correctly ,may needs to be taking out and cleaned, check its in correctly or a broken wire/ poor connection? ,hope this helps Tricky1200

 

[bmwrich58]

Yes I have had the same happen to me. I posted this last year at several sites. By turning the bike off and then restarting the bike,problem solved ans warnings disappeared...so go figure.

 

[JFC]

I had same, triangle, no speedo, constant servo and residual brake on rear - issue was worn rear discs and worn rear pads - pistons out too far and resevoir (rear) too low - new disc and pads and all ok

expect new pads only would have cured it

 

[piebaps]

Thanks fellas. New pads fitted only four weeks ago so looks like thats not the problem.

I will see what the dealer says tomorrow and post what I find out.

 

[piebaps]

Update

Mechanic says he rang BWM and they were aware of the problem and indeed told him to check rear ABS sensor. He replaced this and it all seemed to be OK so it looks like back to the drawing board.

They will collect the bike later this week to investigate further. Meanwhile I am a born again cage driver!

 

[Rhino]

had the same happen to My 06 last year. They ended up replaceing the brake servo as well as the rear wheel sensor as Mine failed and left Me with fully working servo assisted front brakes and no assitst or abs on the back very intresting trying to stop coming off the M1 with a bike that felt that it had a pogo sitck for a rear shock. I had had 2 other brake failiure incidents prior to this where the sensor had been replaced. I will say since having the new servo I havnet had a single brake related problem.

 

[Bones]

Yes I have had the same happen to me. I posted this last year at several sites. By turning the bike off and then restarting the bike,problem solved ans warnings disappeared...so go figure.

This is exactly my experience. It often haoppens if the bike hasn't been used for a few days. If it happens, turn everything off and start again. Sometimes takes a few attempts to clear the fault. Bloody annoying!!!!

 

[bigchris]

For info there is a stupidly placed male/female connector situated by the rear shock and can get easily covered in cack from the road. This is usually zip tied to the spars on the subframe. Get some WD40, and blast it clean. Worked for me about a month ago, and saved a horriffic repair bill.

Definately the achilles heel of the GS, imo.

 

[Flying banana]

I have written elsewhere last year about a similar problem with the rear brake system. The lights start flashing frantically, and the rear servo can be heard constantly running. The only wa it will reset is by stiching the ignition off and on again. It has done it intermittently since early last year, although, to be fair, it went for some months without a problem over ther winter, then did it again twice in succession a couple pf weeks ago.

I suspect it may be summat to do with battery voltage, as it only does it shortly after the bike has started up and not been running for long. I am not entirely sure how good trhe battery is.

Its never becomoe more than an annoyance occasionally now, and I put up with it. The brakes still work, so it'll do me fer now.