Results 1 to 14 of 14

Thread: ABS replacement challenges

  1. #1

    ABS replacement challenges

    My bike is a 2002 R1150RS. Through this forum I connected with someone who sold me a used, correct model ABS pump to replace the one I had which worked only for the front brakes.
    My mechanics have been struggling with getting it to work, they sent this message "We have been able to get the bike to have brakes, but the replacement ABS pump is constantly partially running, like the pump reservoir has trapped air. James has bled it multiple tiles, in different manners to get it to stop, but no avail. It isn't expelling any air anymore, but just isn't quite right. We fear both pumps are not good. The most straightforward approach now may be to eliminate it all together, or install your old one so you can send back the other one to the seller. We can disable the lamp by pulling the relay and that will still allow the power assist to operate. The scantool we are using is not the GS911 but the OBDlink MX+ with Motoscan software. We had picked up a different dongle initially, but it was not able to send and receive long chain commands, which limited the interaction ability with the bike. We can scan the system completely now, but there are no codes that are coming up for the ABS system. Let us know how you would like to proceed with the brakes."

    So, is there a procedure that's being missed? How would I verify that the replacement pump truly is failing?
    I'm reluctant to bypass, but it may be my only option. New replacement is too expensive and rebuild isn't available within the next year (I've checked).

    I'm grateful for assistance.
    Thanks.
    Jeff

  2. #2
    Registered User jrogers's Avatar
    Join Date
    Mar 2021
    Location
    Nor-Cal
    Posts
    27
    Are you using an Independent Mechanic.
    02 R1150R ABS, 04 R1150R, 05 R1100S BCR, 16 S1000XR

  3. #3
    Quote Originally Posted by jrogers View Post
    Are you using an Independent Mechanic.
    Yes, independent mechanics. Unfortunately, the BMW dealer in my area closed and the nearest one is 200 miles away.

  4. #4
    Registered User GTRider's Avatar
    Join Date
    Apr 2006
    Location
    Nibley, UT USA
    Posts
    1,963
    Your bike has iABS (“Whizzy”) brakes that require a very specific bleeding sequence for the two different circuits in the brakes-control circuit and wheel circuit. If your mechanic has never done this before some reading and research are called for, or else take it to a dealer and have them do a fill/flush and bleeding on the system. The control circuits are bled with the bike turned OFF, and the boost pump is used to bleed the wheel circuits-that requires a special funnel so you don’t run the reservoirs dry when using the boost pump for bleeding.

    If your boost pump is running constantly the first thing to check is the microswitches at the handlebar and foot pedal. Those switches are what triggers the boost pump to engage. The boost pump should not engage until the lever/pedal is activated, but you should hear it briefly activate when the ignition is turned on.

    http://users.rcn.com/dehager/service/service_abs3.pdf

    Do a gurgle search for “bmw r1150rs service manual abs brakes” and you’ll find some additional documentation you can download.

    Lastly, are you sure your large turn signal relay is good? BMW runs some brake light functions through that relay and if it fails it can render your boost pump inoperative.

    Best,
    DeVern
    DGerber
    1983 R80ST — 1984 R80 G/S-PD — 2004 K1200GT w/Hannigan S/C — 2010 K1300GT — 2018 R1200GS
    BMWMOA#52184, AMA#271542, IBA#138

  5. #5
    Registered User jrogers's Avatar
    Join Date
    Mar 2021
    Location
    Nor-Cal
    Posts
    27
    Take it to a dealer. I've had talked to my dealer about the ABS brakes on my 02's and he told me he has never had a failure with that system. He has had numerous brought into the shop that someone had screwed up trying to work on them themselves. He was able to fix all of them back to operating properly. We have service ours on two of the bikes we have with that system and while over complicated if you follow the service manual exactly they are serviceable and work good. The dealer also has a better diagnostic than the 911-S.
    02 R1150R ABS, 04 R1150R, 05 R1100S BCR, 16 S1000XR

  6. #6

    ABS pump module switching

    DeVern,
    Thanks for your comments and the pdf.
    I just got this note from my mechanics and interested in your thoughts. They couldn't get any code returns on the replacement module, and it was running constantly.

    "Soooo...

    We plugged in the old ABS unit to check for connectivity of the module.. connected right up. Did a search on need to reprogram the ABS module and came up with multiple plausible answers that point back to one thing. Switching out the module on the two pumps. From what I read, the motors are common to go bad on the pumps, which I believe your rear one did by the look of the fluid weepage that was happening from the old unit. Also, some say the ABS units are interchangeable between like models, but not between different models... ie. RS to RS but not RS to GS, but not confirmed. But definitely confirmed that the dealer has to reprogram the ABS unit module if used and a different module, which Max BMW said might happen, but is a dealer software only issue. So, we're going to switch the module from your old one to the new old one."





    Quote Originally Posted by GTRider View Post
    Your bike has iABS (“Whizzy”) brakes that require a very specific bleeding sequence for the two different circuits in the brakes-control circuit and wheel circuit. If your mechanic has never done this before some reading and research are called for, or else take it to a dealer and have them do a fill/flush and bleeding on the system. The control circuits are bled with the bike turned OFF, and the boost pump is used to bleed the wheel circuits-that requires a special funnel so you don’t run the reservoirs dry when using the boost pump for bleeding.

    If your boost pump is running constantly the first thing to check is the microswitches at the handlebar and foot pedal. Those switches are what triggers the boost pump to engage. The boost pump should not engage until the lever/pedal is activated, but you should hear it briefly activate when the ignition is turned on.

    http://users.rcn.com/dehager/service/service_abs3.pdf

    Do a gurgle search for “bmw r1150rs service manual abs brakes” and you’ll find some additional documentation you can download.

    Lastly, are you sure your large turn signal relay is good? BMW runs some brake light functions through that relay and if it fails it can render your boost pump inoperative.

    Best,
    DeVern

  7. #7
    Left Coast Rider
    Join Date
    Nov 2011
    Location
    Vancouver, British Columbia, Canada
    Posts
    4,202
    Can't wait for the next episode of this mystery.

  8. #8
    Registered User GTRider's Avatar
    Join Date
    Apr 2006
    Location
    Nibley, UT USA
    Posts
    1,963
    RealOEM shows the iABS unit for 2002 R1150RS as # 34 51 7 728 059 which supersedes # 34 51 7 685 790. I could not find a “used on” reference for the 790 unit, but the 059 unit shows as the correct number for R850R & RT, R1150R, Rockster, GS, GSA, RT, and RS as well as the R1100S, R, and RS. That would seem to indicate that the superseded unit should be the same across those models, but one cannot count on that—BMW’s parts fiche is never intended to be a historical reference, just a catalog of the parts they sell NOW for a particular application—and the 059 unit is shown as being available from 12/10/2009 onward. I suppose it’s possible there were differences in the OEM units used on various models and those were resolved into a “one unit to rule them all” back in 2009, but I’ve not seen anything referencing that. And, none of the documentation I’ve seen on replacing the iABS units references a need for dealer programming of the replacement unit—only filling and bleeding.

    There may be others who can chime in on whether there were differences in the OEM iABS units between models, and on the programming question. I’ll reach out to a couple of other sources and see if I can find anything. In the meantime, some questions on background info:

    1. What was the failure mode and indication on your original unit?

    2. Are there part numbers on the two units you have and if so, what are they?

    3. Has the replacement unit been filled with fluid and bled, with key off, using the procedure you’ve been sent in pdf and video? On a replacement it is necessary to fill/bleed the control circuits, with power off, before powering on the bike to bleed the wheel circuits.

    4. As part of the original failure mode, did you observe any anomalies with brake or turn signal lights as part of the failure?

    5. Does the bike have the original BMW signal relay, the big one in the relay box, or is it running an aftermarket relay? I only ask the last two Q’s because I’ve had a “failed iABS unit” on my lift that actually turned out to be a failed aftermarket turn signal relay shutting down the iABS unit.

    Best,
    DeVern
    DGerber
    1983 R80ST — 1984 R80 G/S-PD — 2004 K1200GT w/Hannigan S/C — 2010 K1300GT — 2018 R1200GS
    BMWMOA#52184, AMA#271542, IBA#138

  9. #9
    Registered User Blacque Jacque Shellacque's Avatar
    Join Date
    Nov 2005
    Location
    Pickering, Ontario
    Posts
    302
    My previous ride was a 2002, R1150RS. The iABS failed back in 2008. In my case I had residual braking only, no power what so ever. I picked up a couple of used ones to no avail. One did nothing when I installed it. The other ran continuously and would not initialize. I came to the conclusion picking up used iABS modulators was not a good idea. Eventually I ordered a new unit from Chicago BMW, $1800 at the time. The 2002 RS came with part #34517728059. That part was already superseded at the time, so I received 34517685789. When I compared the two, the "firmware revision" on the electronic module of the new unit was much higher. The brakes with the original unit were always grabby. It seemed when I grabbed the brake, it was either on or off. The new unit was very different. Braking was very progressive with lots of feedback, much like normal brakes. It was a nice bonus, an unexpected improvement.

    The modulators cannot be swapped between models. The RT's brake are fully integrated. Operating either the front or rear brake will result in both brakes working. The RS has partially integrated brakes. Operating the front brake will also turn on the rear, but operating only the rear will NOT operate the front brakes. The realoem website suggests that there were RT's using the partially integrated unit. This was not an option in North America. (but they may have been used on the police bikes) I believe the function of whether the unit is partial or fully integrated is build into the electronic unit of the module. If you were to use one from an RT, you will have fully integrated brakes. I don't know if this would be a good idea as I do not know if the piston sizes of the calipers between RT and RS are the same. I never looked into the GS models and I cannot recall if there were partial or fully integrated. The dealer cannot reprogram these units. Can you imagine the liability if they could, and the dealer messed up! Ouch.

    In my experience there was no magic in bleeding the unit. I never had to use any vacuum tool, I just took my time and bled a lot of fluid. When I installed the new unit, it worked. Simple as that, plug and play. I can only speak of my own experience. Others may have had different results. Getting a hold of a good working used unit isn't easy. My suggestion is to contact this vendor, Module Master. and see what they can do. Try the find my module function.

    https://superactionhero.myshopify.co...md_r1150rs-r22

  10. #10

    follow-up to your questions

    DeVern, below are comments from my mechanics, who seem to be moving towards success.

    " So as a recap to hit on most all points asked. Lack of rear brake operation was the main issue with the bike, upon replacing the ABS unit, bled with key off, bled with key on as per the FSM you left with us. Bike has front and rear brakes, but no ABS actuation. Replacement pump motor is running constantly with key on, re-bled again after cleaning out filters in reservoirs in ABS unit thinking there was a chance that air was trapped in pump. No air in all 4 circuits and clean also. Connected with Motoscan software, would not recognise ABS unit, disconnected new unit, plugged in original unit. Software connected immediately, was able to actuate one circuit, not the rear, code was for pressure modulator, pump motor rear. Found that there had been old weepage from motor to block seam. Decided to swap electronic half of ABS unit after recognizing that the other half was most likely bad on original unit and software would not connect to new unit, but the motor half seemed to work well. Found supporting evidence of people doing the same with other units of the same generation and having issues with one or the other pump motors seizing. The idea that different models may have different programming is speculation from a few people online and I take that with a grain of salt, kinda like peoples opinion with oil. The suggestion with a possible re-program came from a tech at Max BMW in Troy that has had to do that before. We have a set of tamper proof torx plus bits that will be here tomorrow so that we can swap the control units after seeing that it has been done many times safely. So long story short, replacement unit would probably work perfectly on the original bike, or after a reflash with the actual BMW software at the closest dealer 4 hours away, or by swapping the module off of the old unit onto the new unit to allow communication. The signal relay is an OE BMW replacement that looks to be from 2016 by the date on the side of it. All lamps had been checked, connections cleaned at lamps and at the new Yuasa battery you provided for us to install that we activated and then trickle charged to ensure a full charge for computer operation and battery life longevity."
    "the two part numbers are identical to a T"





    Quote Originally Posted by GTRider View Post
    RealOEM shows the iABS unit for 2002 R1150RS as # 34 51 7 728 059 which supersedes # 34 51 7 685 790. I could not find a “used on” reference for the 790 unit, but the 059 unit shows as the correct number for R850R & RT, R1150R, Rockster, GS, GSA, RT, and RS as well as the R1100S, R, and RS. That would seem to indicate that the superseded unit should be the same across those models, but one cannot count on that—BMW’s parts fiche is never intended to be a historical reference, just a catalog of the parts they sell NOW for a particular application—and the 059 unit is shown as being available from 12/10/2009 onward. I suppose it’s possible there were differences in the OEM units used on various models and those were resolved into a “one unit to rule them all” back in 2009, but I’ve not seen anything referencing that. And, none of the documentation I’ve seen on replacing the iABS units references a need for dealer programming of the replacement unit—only filling and bleeding.

    There may be others who can chime in on whether there were differences in the OEM iABS units between models, and on the programming question. I’ll reach out to a couple of other sources and see if I can find anything. In the meantime, some questions on background info:

    1. What was the failure mode and indication on your original unit?

    2. Are there part numbers on the two units you have and if so, what are they?

    3. Has the replacement unit been filled with fluid and bled, with key off, using the procedure you’ve been sent in pdf and video? On a replacement it is necessary to fill/bleed the control circuits, with power off, before powering on the bike to bleed the wheel circuits.

    4. As part of the original failure mode, did you observe any anomalies with brake or turn signal lights as part of the failure?

    5. Does the bike have the original BMW signal relay, the big one in the relay box, or is it running an aftermarket relay? I only ask the last two Q’s because I’ve had a “failed iABS unit” on my lift that actually turned out to be a failed aftermarket turn signal relay shutting down the iABS unit.

    Best,
    DeVern

  11. #11

    thanks for sharing your experience...

    Thanks for sharing your experience, it seems consistent with what's been happening with the units I have. I think we'll solve it by taking the electronic module from the original unit and attaching it to the replacement pump. Indications so far are that's going to work.
    I did check with Module Masters and that would have been my preferred option, but they're backed up for over a year.


    Quote Originally Posted by Blacque Jacque Shellacque View Post
    My previous ride was a 2002, R1150RS. The iABS failed back in 2008. In my case I had residual braking only, no power what so ever. I picked up a couple of used ones to no avail. One did nothing when I installed it. The other ran continuously and would not initialize. I came to the conclusion picking up used iABS modulators was not a good idea. Eventually I ordered a new unit from Chicago BMW, $1800 at the time. The 2002 RS came with part #34517728059. That part was already superseded at the time, so I received 34517685789. When I compared the two, the "firmware revision" on the electronic module of the new unit was much higher. The brakes with the original unit were always grabby. It seemed when I grabbed the brake, it was either on or off. The new unit was very different. Braking was very progressive with lots of feedback, much like normal brakes. It was a nice bonus, an unexpected improvement.

    The modulators cannot be swapped between models. The RT's brake are fully integrated. Operating either the front or rear brake will result in both brakes working. The RS has partially integrated brakes. Operating the front brake will also turn on the rear, but operating only the rear will NOT operate the front brakes. The realoem website suggests that there were RT's using the partially integrated unit. This was not an option in North America. (but they may have been used on the police bikes) I believe the function of whether the unit is partial or fully integrated is build into the electronic unit of the module. If you were to use one from an RT, you will have fully integrated brakes. I don't know if this would be a good idea as I do not know if the piston sizes of the calipers between RT and RS are the same. I never looked into the GS models and I cannot recall if there were partial or fully integrated. The dealer cannot reprogram these units. Can you imagine the liability if they could, and the dealer messed up! Ouch.

    In my experience there was no magic in bleeding the unit. I never had to use any vacuum tool, I just took my time and bled a lot of fluid. When I installed the new unit, it worked. Simple as that, plug and play. I can only speak of my own experience. Others may have had different results. Getting a hold of a good working used unit isn't easy. My suggestion is to contact this vendor, Module Master. and see what they can do. Try the find my module function.

    https://superactionhero.myshopify.co...md_r1150rs-r22

  12. #12
    Left Coast Rider
    Join Date
    Nov 2011
    Location
    Vancouver, British Columbia, Canada
    Posts
    4,202
    Quote Originally Posted by jeff.arywitz@gmail.com View Post
    DeVern, below are comments from my mechanics, who seem to be moving towards success.
    Nice to see that your mechanic is making the effort AND open to suggestion from others. He's a keeper for sure. I'm betting you'll soon be on the road.

  13. #13
    Registered User GTRider's Avatar
    Join Date
    Apr 2006
    Location
    Nibley, UT USA
    Posts
    1,963
    Quote Originally Posted by jeff.arywitz@gmail.com View Post
    DeVern, below are comments from my mechanics, who seem to be moving towards success.

    " So as a recap to hit on most all points asked. Lack of rear brake operation was the main issue with the bike, upon replacing the ABS unit, bled with key off, bled with key on as per the FSM you left with us. Bike has front and rear brakes, but no ABS actuation. Replacement pump motor is running constantly with key on, re-bled again after cleaning out filters in reservoirs in ABS unit thinking there was a chance that air was trapped in pump. No air in all 4 circuits and clean also. Connected with Motoscan software, would not recognise ABS unit, disconnected new unit, plugged in original unit. Software connected immediately, was able to actuate one circuit, not the rear, code was for pressure modulator, pump motor rear. Found that there had been old weepage from motor to block seam. Decided to swap electronic half of ABS unit after recognizing that the other half was most likely bad on original unit and software would not connect to new unit, but the motor half seemed to work well. Found supporting evidence of people doing the same with other units of the same generation and having issues with one or the other pump motors seizing. The idea that different models may have different programming is speculation from a few people online and I take that with a grain of salt, kinda like peoples opinion with oil. The suggestion with a possible re-program came from a tech at Max BMW in Troy that has had to do that before. We have a set of tamper proof torx plus bits that will be here tomorrow so that we can swap the control units after seeing that it has been done many times safely. So long story short, replacement unit would probably work perfectly on the original bike, or after a reflash with the actual BMW software at the closest dealer 4 hours away, or by swapping the module off of the old unit onto the new unit to allow communication. The signal relay is an OE BMW replacement that looks to be from 2016 by the date on the side of it. All lamps had been checked, connections cleaned at lamps and at the new Yuasa battery you provided for us to install that we activated and then trickle charged to ensure a full charge for computer operation and battery life longevity."
    "the two part numbers are identical to a T"
    Jeff;
    That’s a great report from your technician, who sounds like a keeper. I have heard of swapping the electronics from one unit to another but have no direct experience with that, so please report back on that aspect. I’m not familiar with Motoscan as I use GS-911, but I do know that even with identical part numbers the iABS units can have different revisions of firmware, which to me raises the question of dependencies between ECU firmware revision levels and iABS firmware revisions. And along with that, I’m wondering if resolving those by flashing one or both units to compatible levels is what is being called on the interwebs “reprogramming the module to the bike.” That answer is beyond my pay grade and would have to come from a certified BMW technician or service writer, and one familiar with that era.

    As you know from your experience prior to the failure, the normal sequence at key-on is to hear the iABS briefly energize to a ready state, then to hear the ABS reset when the bike is put underway. Without both of those happening ABS will not engage and/or you’ll be left with just “residual braking”, aka no braking at all. And, it is possible to have the boost pump engage when the brake is activated, but still not have functioning ABS. The constant-on boost pump puzzles me; likely not a stuck or misaligned microswitch as it happens with only one of the units UNLESS the old iABS unit has one dead pump AND a stuck/misaligned microswitch for that brake. If the dead brake on the old unit and the brake being energized by the constant-on pump are the same, there is still a chance that the switch or relay could be a problem, I think.

    Lastly, as I said I’m not familiar with Motoscan. I do know that on the 2004 iABS units connecting a GS-911 and using an iPad to view the information results in an abs module reported as “can’t be read” and appears to be MIA. Connecting a Windows PC in that same scenario results in the module being seen and fully reported—codes, firmware revision, etc.

    Please keep us posted as things progress!

    Best,
    DeVern
    DGerber
    1983 R80ST — 1984 R80 G/S-PD — 2004 K1200GT w/Hannigan S/C — 2010 K1300GT — 2018 R1200GS
    BMWMOA#52184, AMA#271542, IBA#138

  14. #14
    Registered User Blacque Jacque Shellacque's Avatar
    Join Date
    Nov 2005
    Location
    Pickering, Ontario
    Posts
    302
    I lied in my original post as I supplied the wrong part number. I recorded the part numbers of the original unit and the replacement.

    2002 original unit FTE S2AB90036 34517663755 HW8 SW05
    2008 replacement 34517660909 HW12 SW12

    It seems there may be quite a few different revisions of these units over the years.

Similar Threads

  1. Replies: 15
    Last Post: 05-04-2016, 10:43 PM
  2. '10 RT - Charting the Challenges....
    By fastbikedroid in forum Hexheads/Camheads
    Replies: 0
    Last Post: 09-28-2011, 11:06 PM
  3. R65 Electrical Challenges
    By kentuvman in forum Airheads
    Replies: 29
    Last Post: 06-19-2010, 01:58 PM
  4. DC Power Design Challenges
    By HIWAYMIKE in forum Hexheads/Camheads
    Replies: 6
    Last Post: 08-21-2007, 03:13 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •