• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

  • Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.

    The Election forum is here: Election Forum

iABS fault code on 2002 R1150RS Genral warning light stays on!

required

New member
My general warning light stays on which I belive means : Gen ON, ABS off = Tail light/brake light defective BUT the tail light / brake light works! Is there a trouble shooting tree on what to look for in what order?:banghead
 
A shorted rear brake switch (or the switch wiring) will will cause this. I had this issue 2 months ago. The brake light continued to work while operating the rear brake in spite of the short. The switch triggers the brake lamp indirectly through the iABS module. Smart circuitry! The insulation had come off the wires where they meet the switch body. I guess dangling the foot peg from the wire too many times didn't help!
 
IF the fault is actually the bulb (and Jacque makes a good point):
A bulb which is about to fail will also trigger the computer to illuminate the warning light, because the current draw is no longer quite inside the spec range.
And, your eyes may be getting faked out - If the tail light actually fails, on some models (I don't recall if yours is included), the Brake light is turned on by the computer, at a lower intensity, to function as a temporary tail light (BMW safety feature).
REPLACE THE BULBS ANYWAY. Or just the one if you can see the filament is broken, or the inside of the glass is smoky.
Also examine the contacts of the socket; if they are corroded or worn, that can trigger a fault too.

Side note: As small as these taillight lenses are, I've replaced both of my bulbs with dual-filament types. Yes it draws a little more current (and most of the LED "replacements" do NOT fill up the lighted area sufficiently), and a GS-911 check will show a fault code due to that, but it won't trigger the bike's computer to show a fault.
 
Well I replaced the bulb to no avail! Tomorrow will be trace the wiring day. It just seems strange that everything functions as it should with the exception of the light being on.
 
Do the easy things first: Lightly lube (WD or Teflon spray) and exercise both brake light switches and listen for their respective faint little click as they move. One (or both...) may just be gummed up or need an adjustment.
 
iABS Faulty

My general warning light stays on which I belive means : Gen ON, ABS off = Tail light/brake light defective BUT the tail light / brake light works! Is there a trouble shooting tree on what to look for in what order?:banghead

I too am having the same exact problem on my 02r1150r. I was getting tired of the on again off again problem so I brought it to the dealer. When they went to turn the ignition on, the fault had cleared and was not registered in memory so they did not know what caused it. I left it there for over a week and it did not come back. I took it home and on the second day it started again only to be cleared the next morning. I replaced the brake light bulb and cleaned the socket. I also checked and cleaned the brake pedal switch. if it happens again, should i pull apart the brake pedal switch? Could it also be an intermittent problem with the rear ABS sensor?
just don't know where to go next. please let me know how you make out.
 
Slow: When you manually move the rear brake pedal with your hand, can you actually hear the faint "click" of the switch as it makes and breaks contact? It must be adjusted so that you do, every time.
And there is another switch up inside the front brake lever - same check, but more difficult to hear; maybe you can see the brake light from that position or observe a very slight dimming of other lights as the brake light comes on.
 
"Could it also be an intermittent problem with the rear ABS sensor?"

I believe a faulty sensor should give a different warning. Gen OFF, ABS flashes at 1Hz = ABS not available. Pull-away test not completed.

Unfortunately, just because a switch goes, click, click, doesn't mean it works. Its probably rare, but its still possible for the contacts in the switch to be defective. If you have an VOM meter, you can pull apart the rear brake light connector and check it for resistance. The connector is tie wrapped to the frame on the RH side near the clutch bleed pipe. Set the VOM to lowest setting for ohms and connect the test leads to connector and operate the switch. You should see very little resistance with the switch closed. It's backwards, so when you apply the brake, the switch opens, and resistance should be infinite.
 
"Could it also be an intermittent problem with the rear ABS sensor?"

I believe a faulty sensor should give a different warning. Gen OFF, ABS flashes at 1Hz = ABS not available. Pull-away test not completed.

Unfortunately, just because a switch goes, click, click, doesn't mean it works. Its probably rare, but its still possible for the contacts in the switch to be defective. If you have an VOM meter, you can pull apart the rear brake light connector and check it for resistance. The connector is tie wrapped to the frame on the RH side near the clutch bleed pipe. Set the VOM to lowest setting for ohms and connect the test leads to connector and operate the switch. You should see very little resistance with the switch closed. It's backwards, so when you apply the brake, the switch opens, and resistance should be infinite.

Thanks. I wanted to try to elimate one more potential problem area so i found a rear brake switch on ebay. The seller said it was from an r1150r with only 20k miles. I installed it this past weekend. Here is hoping this was the issue. If you don't believe it could be the ABS rear wheel sensor, than i don't know what else I can do. Evereything else looks O.
 
Ok, I'm going to be the guy who overthinks this problem.

Check for play in your final drive. Just had a friend who experienced a similar issue, left it alone because they were going on a trip...and had the FD bearings self-destruct halfway into the trip.

Turns out the initial play in the FD caused the ABS sensor to rub up against the exciter disc resulting in the ABS fault. Not saying that this is your issue, just that it could be.
 
Ok, I'm going to be the guy who overthinks this problem.

Check for play in your final drive. Just had a friend who experienced a similar issue, left it alone because they were going on a trip...and had the FD bearings self-destruct halfway into the trip.

Turns out the initial play in the FD caused the ABS sensor to rub up against the exciter disc resulting in the ABS fault. Not saying that this is your issue, just that it could be.

My final drive was replaced about 25k miles ago and is in good shape. Thanks for thinking outside the box.
 
I have a friend with a GS911 lined up but I just had something strange happen with the light. I put the bike up on the center stand to check the oil etc. and when I started it up the light went off and stayed off for about ten miles. :scratch
 
Back
Top