ABS failure on r1100rt

[old_farmer]

Hello. I have a 99 r1100rt that I have owned since new, with a bit over 8K miles (no time to ride).

 

About a year ago the ABS failed. I was riding in town and had a brain fart (thought I was in first but really was in second) when starting from a stop. The engine stalled, and then I had the alternating flashing lights which have been going ever since.

 

Battery is original, but I think it is good (last check it was reading 12.5V after sitting a week). I keep the thing on a battery tender fairly frequently.

 

I have done brake fluid changes , although probably not as frequently as I should. I use a Mity Vac. I don't recall having any problems last time I changed the fluid, e.g. I don't think anything happened that might have got air in the system.

 

Here's the interesting part. I called the "local" (>100 miles away!) dealer to schedule a service and have them look at the brakes. I described the problem to the service guy and pointed out that I had been changing the fluid myself. Upon hearing that, he said something to the effect of "that could be the problem, you need to leave that to the pros with the computers yada yada...". He also raised the possibility of a failed modulator ($1700!!) caused by my incompetence.

 

This doesn't seem to add up. I can read many posts here where folks are doing the fluid changes just as I did with no problems whatsoever. Also my ABS failed about a year after the last fluid change. I don't see the connection.

 

Your thoughts, please?

[PRC]

Here is a thread about the same issue

 

R1100RT Abs Lights Hope this helps

[wolcott]

Old Farmer: About time to change out that original 1999 battery and pick up a panasonic or odyssey absorbed glass-mat (AGM) battery for starters, IMHO. I think Digikey has the panasonic batteries; for odyssey batteries you will have to do a search. I put in a PC 680 odyssey in my '98 RT when I kept getting ABS light faults upon starting up my bike. Of course, it is possible you do have other problems; however, with a battery that old you risk the chance of breaking down, never a pleasant thought.

[John Dickens]

Exactly the same thing happened to me. I stalled the bike and the ABS lights came on. I reset them and they stayed off a couple of hours but came on again.

Eventually resetting made no difference at all so I read out the fault code. It was code 3, front ABS sensor.

I couldn't see how stalling the bike could affect the sensor but I changed it anyway and the ABS is now working spot on again.

[JohnBeaven]

My guess is that the battery is knackered. Seven years is pretty old for a battery. An auto electrcian told me recently that anything over three years is a bonus.

Check how much the battery voltage drops during start up. If it drops too much the ABS will fault.

[Green RT]

You don't indicate whether you have done a hard reset. If you haven't you definitely should before you look any further.

 

Soft reset: Turn off key and restart the bike.

Hard reset: Ground pin 2 (middle pin) of diagnostic connector (with blue plug) under the seat behind the fuse box. Turn on ignition (don't start bike), hold down abs switch for 8 seconds, then turn off ignition, release abs switch, remove ground.

[old_farmer]

Thanks to all of you for your help. I did the 8 second ground reset and that did the trick. And I verified actual function on my gravel driveway.

 

Next step is to pop for a new battery just to ensure I don't have voltage related gremlins contributing to this.

 

Thanks again