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Discussion Starter #1
Interesting issue. Still trying to dope out what it is.

Bike starts normally. Everything fine until I step on the rear brake pedal and the dreaded red triangle pops up (solid - no flash). It stays lit till shut down and restart and the same thing all over again. As an experiment, I did 20 mins w/o touching the rear brake pedal and everything was jake. As soon as I step on the pedal, the triangle appears.

Seen it before? Any ideas? Come on "brain trust", help me out here...
 

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Interesting issue. Still trying to dope out what it is.

Bike starts normally. Everything fine until I step on the rear brake pedal and the dreaded red triangle pops up (solid - no flash). It stays lit till shut down and restart and the same thing all over again. As an experiment, I did 20 mins w/o touching the rear brake pedal and everything was jake. As soon as I step on the pedal, the triangle appears.

Seen it before? Any ideas? Come on "brain trust", help me out here...

Yes, I have seen this before - I even provoked the system into that mode to better understand the IABS system behavior for various faults.

The solid (no flash) Red-Triangle warning can appear in combination with a flashing or not flashing (slow or fast) ABS-Warning (the other Red warning). In your case, based on behavior and circumstances that you have described, I would say 90% sure it is a non-functioning rear brake switch.

For IABS (ABS with electrical servos) a rear brake-switch defects can include the following cases:

(1) If either front or rear brake switch is unplugged, it will cause a fault during self-test (withing 6 sec after ignition ON)
(2) Any cut wires in the brake switches circuit will have same effect as above

(3) On the other hand, if switch is connected but does not "click" when brake lever is pressed, you will get another type of IABS fault. Internally, the IABS modulator is able to measure fluid pressure coming from lever (or pedal) - when you reach a certain pressure (light to moderate), if the brake switch has not been activated at that point, it is considered an anomaly. This is why normal behavior is the switch should activate fairly early in lever travel.

CONCLUSION: I am assuming that your switch is plugged, no wire is cut, but the switch never "click" when pedal is pressed. You can confirm visually but switch is well hidden and even with engine OFF, the mechanical "click" is not very loud. Another way is to trace the switch connector and check continuity. On IABS system, these have reversed logic (continuity when pedal is at rest AND no-continuity when pressed).

IMPORTANT: make sure to check procedure to check pedal and switch adjustment as per shop-manual (or Clymer). This is critical for IABS system - otherwise you may have constant servos motor activation even when pedal is not touched.

Let me know what you find...
 

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Wrencher Extraordinaire
2005 K1200LT
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I am surprised John missed this one. The steady triangle with no blinking ABS warning is usually the rear light is out (center bulb). Not sure why it only happens when you hit the rear brake. Worth checking (hold over from the RS with only one tail/stop bulb).

From the riders manual:
 

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I am surprised John missed this one. The steady triangle with no blinking ABS warning is usually the rear light is out (center bulb). Not sure why it only happens when you hit the rear brake. Worth checking (hold over from the RS with only one tail/stop bulb).

From the riders manual:
John,

I am aware of this bulb burned warning (and did not miss thinking about it as a 1st option ). BUT... the fact that his red-triangle only goes ON when he hit the pedal had me choose the 2nd case.

Try it in your garage if yo ever have time - no need for engine to run. However, on the K1200LT it is not easy to simulate this as the switch is quite hidden - you have to fake a temp mechanism to hold it steady for the test purpose while pedal is pressed.

If you have a GS911, you should also read one of these fault codes when this scenario happens for the REAR brake switch defect:
4410: Fault active brake
4430: ABS fault
 

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I humbly bow to your knowledge, Oh John of Canada! I just tried it and you are absolutely correct. I held the brake switch paddle (simulating a stuck switch) and pushed the pedal down and the red triangle came on. I'll file that one away for sure. Thanks.
 

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Could it also be a dying or low battery?
When my Odyssey started to kick the bucket I would get the solid triangle after starting the bike. I suspect this could also happen without starting the bike by pressing the brake pedal thus creating a load on the battery.
This would not however explain why it happens using just the rear brake pedal.
Sorry, that's the best I got!:D
 

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I humbly bow to your knowledge, Oh John of Canada! I just tried it and you are absolutely correct. I held the brake switch paddle (simulating a stuck switch) and pushed the pedal down and the red triangle came on. I'll file that one away for sure. Thanks.
Thanks for the kind words but you may have to take that back ;-) Let me explain...

While reading a dealer's Service-Bulletin on certain IABS faults, I got the idea that maybe the system is activating the brake light either (1) with brake switch or either (2) with pressure even if the brake switch does not "click" (front or rear).

Was easy to confirm while testing in Garage and holding the switch at same time. But, at that point I saw a Triangle fault... hum... interresting I said to myself. Reading resulting fault from a GS911 point a view gave me a fault code and a corresponding error message.

BUT.... I am a perfectionist and these findings are incomplete. I just found this recently and I have yet done a ride with switch in that state to see how the other ABS-warning will behave once bike is at running speed (after a positive self-check). This is the exact condition in which this thread started when he was describing his problem in 1st post.

Will try to test this next Saturday.
 
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I humbly bow to your knowledge, Oh John of Canada! I just tried it and you are absolutely correct. I held the brake switch paddle (simulating a stuck switch) and pushed the pedal down and the red triangle came on. I'll file that one away for sure. Thanks.
JOHN (Jzeiler),
OK... just came back from a ride with REAR brake switch tied as described in previous posts of same thread.

The ABS-warning will stay OFF if you delay REAR brake application until bike is at running speed (after a positive self-check and after you had covered a few feet). This is the exact condition in which this thread started when he was describing his problem in 1st post.

If you apply REAR brake just after starting the bike (before moving), then the same condition will be visible (Red TRIANGLE ON - not flashing) After moving, the the other ABS-warning will go off as usual. In all cases, the RED triangle will stay ON until next ignition OFF/Ignition ON cycle. A permanent ABS-fault will stay in memory that you can read with GS911 or dealers computer (17917: Defective REAR brake switch)

What will confuse many with this undocumented ABS-warning combination is:
(1) the 2 RED warning will behave very similar to a failure of center tail-light (except only in context of brake pedal application). When bulb is defective, the RED Triangle goes ON during IABS self-check (2 to 5 sec after ignition ON)

(2) BMW could have selected another pattern that was not already used for a specific IABS fault, like both RED warnings ON steady

No time to test same thing with FRONT brake switch now because it requires more dis-assembly than rear to bypass switch. Will wait until I have some throttle cable or other maintenance items during quiet winter months.

CONCLUSION: as stated in earlier post, the OP (UncleMark) has a defective rear brake switch -OR- the metal-tab attached to switch is not being activated by the pedal.
 

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Thanks for checking that out for us John. I will add that to my check list.
 

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Discussion Starter #11
CONCLUSION: as stated in earlier post, the OP (UncleMark) has a defective rear brake switch -OR- the metal-tab attached to switch is not being activated by the pedal.
Aw crapola... Now I have to undress the big girl, fiddle with the switch and do the other 200 things I had planned on while I was in there... <sigh> You guys just make me wanna cry... :D

Me thanks to all... as always an expert diag... If I find any gold coins under her skirt, I'll let'cha all know and then pass them around. You tech guru's on this forum don't get paid enuf as far as I am concerned...
 

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Aw crapola... Now I have to undress the big girl, fiddle with the switch and do the other 200 things I had planned on while I was in there... <sigh> You guys just make me wanna cry... :D

Me thanks to all... as always an expert diag... If I find any gold coins under her skirt, I'll let'cha all know and then pass them around. You tech guru's on this forum don't get paid enuf as far as I am concerned...
If you insist to pay, I will send my PayPal address in a private message. ;-) LOL

Either it will be obvious (like metal tab broken or jammed -OR- either you will have to use OhmMeter plugged to end connector to confirm switch is "kaput" (if it work, it should have no continuity when "clicked").

Let us know what you find...
 

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Uncle Mark is actually gonna ride his bike again, after hibernating the last 21/2 years? Awesome, we at EXR miss you!:crybaby:
 

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I have a slight variation on the problem in this thread. The Red Triangle light only comes on when I touch the rear brake when turning. When I use the brake moving straight ahead I get no light. I can't think of a good reason why that would make a difference other than fluid levels, and I have topped them off with no change.
 

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I have a slight variation on the problem in this thread. The Red Triangle light only comes on when I touch the rear brake when turning. When I use the brake moving straight ahead I get no light. I can't think of a good reason why that would make a difference other than fluid levels, and I have topped them off with no change.
Fluid levels usually result in a wig wag light, and the early iABS reservoirs were very sensitive to fluid levels so yes they could activate in a turn. Try adding a bit more fluid to both halves.
 

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I've been riding with minimal use of the rear brake, but decided to follow some of the suggestions. I first replaced the battery which was a bit long of tooth anyway. Took it for a ride and still have the problem. I then topped off both back reservoirs. Took it for a ride, same problem. Time to tear the old girl apart and replace the rear brake switch. What a pain. Set the switch at 14mm as measured by my 14mm wrench. Turned the ignition on and AW SHIP!!!!!! Now when I touch either brake, the ABS starts to squeal and won't shut off until I turn the key off. I'm not sure where to look for this. The brake light follows the pedal movement (Rear) on when down and off when up. (Front) on when squeezed off when released. Does anyone have an idea what I might have done wrong? It does the same whether the engine is running or not. Need help please...I just sold my other tourer and don't want to ride my 750 Virago from Illinois to Montana and back.
 

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I just got back from a test ride after replacing the rear brake lines and wah-lah the problem is resolved. I drove the old girl over to Iowa City and had them check for errors and the only errors they could find were a Battery problem because I just replaced the battery and a rear brake switch problem because I just replaced the rear brake switch. He cleared the errors and they did not return. The technician suggested that I needed to spend the $750 to have the brake lines replaced because the rear brake wasn't letting go completely. I drove her home and ordered the Spiegler kit. It came yesterday and I replaced the two rear hoses today and then bled the rear abs and caliper systems. It now works like a champ. I'll do the front in the spring when I tear it down to do it's annual maintenance.
 
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Glad that did it for you and thanks for the follow up report.
 

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Latest update: I made the trip from home (Illinois) out to Billings and back through Yellowstone. About 3000 miles total. I didn't notice any problems other than quite a bit of brake dust on the rear wheel. The rear tire was due for replacement so I took it in to Countryside, IL to have that replaced. About 10 miles from my destination the hated "RED TRIANGLE" returned and my rear brake refused to release. I got it off the road and called the dealer. They said that the only thing they could find in the computer was a problem with the rear brake switch. I am skeptical about this being a permanent fix because I had already replaced the brake switch and adjusted it according to the Clymer manual, but it does seem to be working now. ($588 parts and labor not counting the rear tire. )
 

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Discussion Starter #20
OK... I have been dually chastised for not responding about what the issue actually was. I have been flogged! I apologize...

Here's what I found,

I have a BlueSea connected to the battery and I use that to distribute power to several LED devices, as well as PIAA's and another set of floods facing forward. I use a switch to ignite the relay that then sends power to the BlueSea. (I don't like having all my battery power going to lamps and accessories until I tell it to) 6 year old battery still going strong. Must be doing something right...

Anywho, since the big girl was undressed, I did a full service, changed a few things around and in the process, checked the micro switch, rear bulb, brake fluid, flux capacitor... It all seemed to be OK. Redressed her and same issue. Only now I have developed a weird power issue. Undressed and combed through the whole setup. Issue not there now. Redressed her and she was fine for about a month. Had to put her up for 5 months while I was away. Started her up and the power issue was back in full force. Back on a ramp. Undressed her... Ammeter says there is 13.3 volts at the battery, but 6.84 at the BlueSea. WTF? Decided to pull the BlueSea... As I tried to get the 20 amp fuse out of the power lead, it came apart in my hands... It literally shattered into a bunch of pieces. Replaced the power lead with a new fuzeable setup and the issue is gone. No more red triangle and all devices work as before. Inspection of the fuzeable link showed massive corrosion inside the fuse holder. Melting? Not sure. But that fuseable link that provided power to the BlueSea fuse box was giving the rest of the system fits.

That was over 4 months ago. All is well now. No triangle... No issues.... (sigh)

So there you have it... Now all pluggable connections have a good coating of dielectric grease... Don't want that happening again....
 
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