brake failure light

[dave y]

Have a question on a new to me '05 R1002RT w/ABS.
Key on, the brake failure light is blinking at 1/sec freq.
Apply front brake, the triangle warning light is on and the brake failure light blinks at the 4/sec freq.


PO suggested that low battery can cause this. 
I had put it on charger and it was indicating full charge. Lights all bright and engine starts easily. 
:grave:
Suggestions for next steps appreciated. 


Thanks in advance.


Dave

[rglassma]

Check both the brake fluid reservoir in the front and the back of the bike.  If the fluid is low on either, it could cause it.  Also, the brake warning will come on when the bike first starts until the bike starts moving forward.  You may have already checked these things, but I figured I would mention them anyway.  The next step is to put it on the computer to see what else is going on.

[slowvet]

I'm new to RT ownership as well and the brake failure red light flashes immediately on start up then go's away after I roll a few feet. Mine is an '11. From what I've read and learned from these cats on this forum is that it's normal.

[Spencert231]

Well Slowvet, I have been called many things, but never a cat surely that's an old 'beatnik' phrase from the sixties or even earlier. You just reminded me of the old TV Series 77 Sunset Strip, wow now that's going back sometime, do you cats remember it? Hey this is catching

[dave y]

An update. 


Have checked the fluid levels.  OK


Brake Failure light goes out as I pull away but as soon as brake is applied, the red triangle lights solid and the Brake Failure lights blinks at the 4/sec frequency.


The rear pads are worn (one side more than the other) but still have a ittle life showing. 
Will replace tomorrow anyway. 


Thx,


Dave

[BMjoe64]

Well Slowvet, I have been called many things, but never a cat surely that's an old 'beatnik' phrase from the sixties or even earlier. You just reminded me of the old TV Series 77 Sunset Strip, wow now that's going back sometime, do you cats remember it? Hey this is catching

Cats remind me of Topcat, and things like "hi there TC",  the indisputable leader of the gang, plus officer Dibble etc.

Hope you get it sorted Dave, presumably there is nothing in the owners manual which helps?

[slowvet]

Well Slowvet, I have been called many things, but never a cat surely that's an old 'beatnik' phrase from the sixties or even earlier. You just reminded me of the old TV Series 77 Sunset Strip, wow now that's going back sometime, do you cats remember it? Hey this is catching

Wait a tic, I didn't say "older cats"! I guess I was showing respect from what I've learned here . My surf/skate slang slipped out.

[stelyn]

Well Slowvet, I have been called many things, but never a cat surely that's an old 'beatnik' phrase from the sixties or even earlier. You just reminded me of the old TV Series 77 Sunset Strip, wow now that's going back sometime, do you cats remember it? Hey this is catching

Spencer,  yet another one of your `purrrfect' replies..... :whistle:

[dave y]

An update.  Have checked the fluid levels.  OKBrake Failure light goes out as I pull away but as soon as brake is applied, the red triangle lights solid and the Brake Failure lights blinks at the 4/sec frequency.The rear pads are worn (one side more than the other) but still have a ittle life showing.  Will replace tomorrow anyway.  Thx,Dave




Update to my update:


I put new pads on today. 


Made sure battery was full charge (12.9 no load, 13.7 at idle).


Start engine and bike goes through check, and brake failure blinks at 1/sec.
Pull away and light goes out.  Ah, the sweet look of success.


But not to be.


Put on brakes and Warning Triangle comes on solid red, and brake failure blinks at 4/sec.


Rear brake has little effect. Press hard on pedal but little stopping power.  Front seems fine.


Dave

[guest2360]

Don't want to unnecessarily worry you but it could be an ABS fault. Would suggest only a dealer can give you an answer. As your bike has servo brakes are you holding the brake lever on before starting the engine and keeping it on until it sets.. You need to or the serve wont set itself.. You should also hear the servo fire up.

[dave y]

Thx


Can hear the servo running and have been able to rule out low battery voltage.


The manual indicates that solid red warning and 4/sec brake failure blink would indicate that 'only residual braking function is available in at least one circuit'.  Front seems fine, which leads me to the rear which is where the symptom presents itself.


I have one more long shot, would like to put before the wisdom of the collective group. 


The bike was trailered on a tilt bed snowmobile trailer.  Fairly steep incline backing it off (and it has a sidecar attached), so once the trailer goes over the tipping point it's a fast trip and quick stop when the bed hits the pavement.


Is it a possibility that the combination could have jostled the fluid in the rear module enough to have introduced air in the system?


Apologies for all the questions. My first BMW, and out of three dozen bikes in the garage, first experience with ABS.




Dave

[guest2360]

My advice would be.  Because we are talking brakes, don't mess.  Get the bike plugged in and see what faults show. Servo/ABS units are made if gold dust and shouldn't be poked or prodded. 

[dave y]

Anyone done the ABS servo elimination on an '05 RT? 


The hydraulics are a pretty straight forward conversion which gets the bike back to good standard brakes.
Would like to avoid cutting the plug and adding the relays as that doesn't address the speedo and the warning lights. (And would like to save the connector in tact in case ever decide to put it back to original).


Going to ping the GS list as there is some dated discussion there on keeping the plug/connector in tact.


Thx,


Dave

[STeinar]

Thx


Can hear the servo running and have been able to rule out low battery voltage.


The manual indicates that solid red warning and 4/sec brake failure blink would indicate that 'only residual braking function is available in at least one circuit'.  Front seems fine, which leads me to the rear which is where the symptom presents itself.


I have one more long shot, would like to put before the wisdom of the collective group. 


The bike was trailered on a tilt bed snowmobile trailer.  Fairly steep incline backing it off (and it has a sidecar attached),so once the trailer goes over the tipping point it's a fast trip and quick stop when the bed hits the pavement.


Is it a possibility that the combination could have jostled the fluid in the rear module enough to have introduced air in the system?


Apologies for all the questions. My first BMW, and out of three dozen bikes in the garage, first experience with ABS.




Dave

Air in the servo ?

Helped a friend ones, and did a full flush of the whole system - also all the servo part.

After that - all was ok.

Another thing - check that the happening has not damaged the wiring from the speed sensors. If so it will show up like yours.