Got the Dreaded ABS Red Brake Failure Light 2007 R1200RT

[WestHautianPlen]

The Bike: 2007 R1200RT 21K miles. Has had brake line and cable recall performed.

I am a little on the nauseated side as I write. I rode over to the in-laws yesterday evening and on the way the Brake Failure light blinked and then stayed on. Paranoia set in immediately, tried both the front and rear brakes independently and both worked but the rear seamed to require a little more pressure. I tested the brakes several times hoping it would reset or clear. On the way back home I realized that the ABS was not working, because I could lock up both the front and rear tires. After I arrived home I checked the front Brake fluid level via the sight glass and it was filled to the tip of the glass. I check the rear brake level and it was at the top. I check the brake lights and both lamps were working. I checked the cables from the rear Final drive and from the front sender unit and both appear to be without any physical damage. I started the bike and as it idled the brake failure light blinked like normal so I proceeded out of the drive the blinking brake failure light went out until I applied enough pressure to lock the rear tire and then the dreaded brake failure light came on and stayed on again. I have turned the key of and restarted the bike, however the failure light stays on. I disconnected the battery in an attempt to wipe the fault, but the light stayed on.

Now for the $3500.00 question of the day. Is there anything else I can check prior to scheduling a service?

[andy57]

Basically the same thing happened to my 07 GSA two weeks ago, new abs pump $1325 later dealer had it fixed. good luck

[deilenberger]

Plen - several things:

Please read: http://www.bmwmoa.org/forum/showthread.php?t=46055 - I've added that info to your thread title. It's important info as hexheads have had two different (completely different) brake systems. It's also useful for people who may be searching for this info in the future. Please do add this info to thread titles when posting in the tech sections.

On to your problem..

You mentioned you checked the brake light... did you do this by removing the bulbs and checking the operation of them? The hexhead is smart enough that if the brake light burns out, it will run the normal running light at 1/2 power, and only brighten it when you use the brake.. so it LOOKS like you have a brake light, even though the brake bulb could well be burned out.

To really check them - take the sockets out of the taillight and watch what happens when you turn the bike on, and then hit the brake.

Disconnecting the battery will do nothing if the fault remains. To do anything useful, a code-reader like the dealer has, or you can buy (GS-911) is really needed to determine why the system has turned on the warning light.

FWIW - some people have fixed the ABS/Brake-module by cleaning the electric motor on it.. it sounded as if in some cases the brushes in it may get dirty enough that they start to bind in the holders and don't make good contact with the amature. They also don't seem to fail all that often, so a good used one shouldn't be awfully hard to find, or too expensive.

Can we assume the semi-annual brake fluid flushes have been done (the clock starts when the bike is manufactured and should be done every two years from that date..)?

[WestHautianPlen]

Plen - several things:

Please read: http://www.bmwmoa.org/forum/showthread.php?t=46055 - I've added that info to your thread title. It's important info as hexheads have had two different (completely different) brake systems. It's also useful for people who may be searching for this info in the future. Please do add this info to thread titles when posting in the tech sections.

On to your problem..

You mentioned you checked the brake light... did you do this by removing the bulbs and checking the operation of them? The hexhead is smart enough that if the brake light burns out, it will run the normal running light at 1/2 power, and only brighten it when you use the brake.. so it LOOKS like you have a brake light, even though the brake bulb could well be burned out.

To really check them - take the sockets out of the taillight and watch what happens when you turn the bike on, and then hit the brake.

Disconnecting the battery will do nothing if the fault remains. To do anything useful, a code-reader like the dealer has, or you can buy (GS-911) is really needed to determine why the system has turned on the warning light.

FWIW - some people have fixed the ABS/Brake-module by cleaning the electric motor on it.. it sounded as if in some cases the brushes in it may get dirty enough that they start to bind in the holders and don't make good contact with the amature. They also don't seem to fail all that often, so a good used one shouldn't be awfully hard to find, or too expensive.

Can we assume the semi-annual brake fluid flushes have been done (the clock starts when the bike is manufactured and should be done every two years from that date..)?

Thanks for letting me know about the bike info in the Title Line.

1) Yes the Indy dealer flushed the brake system for both front and back when they performed the brake line recall late last summer.
2) I will check the brake lamps today.
3) If the lamps are not the problem, I will pull the plastic off look at the ABS unit and associated wiring.

Thanks for your help.

[nplenzick]

Plen - several things:



FWIW - some people have fixed the ABS/Brake-module by cleaning the electric motor on it.. it sounded as if in some cases the brushes in it may get dirty enough that they start to bind in the holders and don't make good contact with the amature. They also don't seem to fail all that often, so a good used one shouldn't be awfully hard to find, or too expensive.

e..)?

There's an electric motor on the ABS for 07 and latter?

[dmftoy1]

Don't know if it helps but I saw a thread either on here or advrider.com about a company who repairs these now. Good Luck!

[RapidRoadRescue]

I just had a 06 gs with ABS pump issue ,it turns out it was not a bad ABS pump at all.In last 8 months I replaced 2 bad ABS units on beemers.I no longer use dealer to service my bikes since I can scan the codes by my self.
On the last bike I worked the Big store diagnosed as a bad ABS unit where it turns out to be something very simple.

I'm few hours north from you but feel free to PM me and I will send you my contact #.

[Sailorlite]

Plen - I'd take a look at the wire from the front ABS sensor to make sure it hasn't been intermittently rubbing on the brake rotor.

[ponch1]

Plen - I'd take a look at the wire from the front ABS sensor to make sure it hasn't been intermittently rubbing on the brake rotor.

That happened to me last year and was an easy fix.

[deilenberger]

There's an electric motor on the ABS for 07 and latter?

Yes. But it's not used for power boost like the earlier whizzy systems did.

[deilenberger]

I just had a 06 gs with ABS pump issue ,it turns out it was not a bad ABS pump at all.In last 8 months I replaced 2 bad ABS units on beemers.I no longer use dealer to service my bikes since I can scan the codes by my self.
On the last bike I worked the Big store diagnosed as a bad ABS unit where it turns out to be something very simple.

I'm few hours north from you but feel free to PM me and I will send you my contact #.

Good on scanning the codes. Your '06 has the older whizzy power-assist brake system, which is quite a different beast then the system BMW started using in '07... Just a FWIW. What fixes yours may not fix the later systems. What are the "ABS units" if not the ABS pump assembly?

[deilenberger]

Plen - I'd take a look at the wire from the front ABS sensor to make sure it hasn't been intermittently rubbing on the brake rotor.

Great suggestion. I believe there was a service bulletin on exactly this for a few hexhead models (not the R12R so I pretty much ignored it..)

[RapidRoadRescue]

Good on scanning the codes. Your '06 has the older whizzy power-assist brake system, which is quite a different beast then the system BMW started using in '07... Just a FWIW. What fixes yours may not fix the later systems. What are the "ABS units" if not the ABS pump assembly?

I was talking about ABS module/pump.

The fix on the 06 gs was faulty micro switch under front brake lever,on 04 gt was bent brake pedal that did not retract all way up allowing tho electric motor to run all the time what caused to fail .

[WestHautianPlen]

Thanks for all of the help. I checked the brake lights this morning and they both appeared to be ok, but I picked up new lamps for the break lights while I was in town and will change those out and clean the socket contacts tonight. I will inspect the front and rear sensor wiring also.
I will report back.

[WestHautianPlen]

Thanks for all of the help. I checked the brake lights this morning and they both appeared to be ok, but I picked up new lamps for the break lights while I was in town and will change those out and clean the socket contacts tonight. I will inspect the front and rear sensor wiring also.
I will report back.

1) Changed rear brake lamps, both elements in the originals were ok.
2) Removed plastic, examined sensor wiring back to connectors, could not find any abrasions or even a potential to rub brake disk, cable keepers were all in place. Ok
3) Manipulated wiring associated with ABS termination board.

Here is the sequence of test I tried to see what would happen:

1) Start the bike, Brake failure light flashes. Good
2) Pulled in front brake lever, pushed on rear brake lever while stationary, Brake failure light still flashes.
3) Shift into gear and take off down drive, Brake failure light go out. Good. Then out on to street.
4) Used both brakes front and rear several times no Brake failure light. Good
5) Did a couple of hard stops using front brake with no brake failure light.
Then Push on rear brake pedal with increased pressure each time until enough pressure was used to lock up rear wheel, and I then get the Brake Failure Light on Constant. Will not reset until bike sets for a while, in the instant case 1.5 hrs.

Anyone have any thoughts to share?