2004 Strange Servo ABS issue

[LukeBarton]

@ Luke - what a small world - im FMC DTC too, i can see your CDSID. Im a G7 PT NVH Eng

Ive just read your comprehensive reply, thank you very much for taking the time to write that! It sounds like this is the exact thing i am going to have to do. I can see the modules on the CAN and thought id never be able to reprogram these without specialist equipment but youve found a way around that. My OBD leads are all USB so i was just about to buy a BT version so i can plug it into the convertor lead to the BMW. Is yours a fancy one or just a cheap £10 ebay one? On my USB one i can switch between MS/HS CAN and im assuming the GS just needs the MS @ 125,000kb/s as there would be no need for a HS on a bike.

I noticed also about the wheel speed sensors going to the ZFE on non ABS. Im guessing the ABS module is not a terminating node? If it was i can just add the resistor as required.

later on i will research the parts needed that you describe and look at going down that route.

Thank you very much for your reply again, Im sure one day we shall cross paths

Mark

Yep, small world!

I went for the OBD MX adapter as recommended by Motoscan, I regularly use it on cars too, works very well. Could always code yours up at Dunton one lunchtime, is only a five minute job. The ABS module isn't a terminating node so can be safely removed. If you want any help/advice when you come to do yours, give me a shout. I also have a small stock of the correct pins for the ZFE multiplug and have the wiring diagrams if you want them, PM me your CDSID and I'll email them over.

Thanks

Luke

Sent from my SM-G965F using Tapatalk

 

[Popell]

Congrats For the work you put in solving this problem.
It seems there is decent option now for post removal effects!

 

[Ajay]

Hi All,

Been reading this with interest as I am too in the same boat.

My issue is that after fiiting the rear subframe back to complete some other work I bled the brakes via the servo but after getting that sorted when I apply preasure to the rear brake pedal one of the brake lines pops out of the servo. Done this 3 times now, twice while riding.

Rather than try and sort the "time bomb" out I am thinking it might be easier to remove it.

What is the opinion on letting the insurance know, because mine is due (sods law)

Is it best to get the kit from Motorworks to sort the pipework out?

Cheers

You must tell insurers of this modification. Forum reports say insurers accept this, certainly the case for me, with Carole Nash, and Bemoto. - changed provider shortly after this mod this year.

Unless you are proficient in making up brake lines, may as well get the Motorworks line. Mate of mine made a line for me, however after fitting I realised the line from the front m/ cyl was long enough to fit directly to the union below the headstock (aftermarket line as I have bar risers). So, you could replace the m/cyl line with a slightly longer one

Did not replace the rear line, original long enough for direct fitment to rear master cyl.

 

[Steptoe]

when I apply preasure to the rear brake pedal one of the brake lines pops out of the servo. Done this 3 times now, twice while riding.



Cheers

Easy. What you've done is put the retaining clip into the wrong slot which spreads the clip so it isn't keeping the brake pipe in place.
Easily done if it's the first time you've removed/replaced the servo pipes

Remove the clip and put it into the next slot 90 degrees further around.

 

[Steptoe]

Did not replace the rear line, original long enough for direct fitment to rear master cyl.

I make the solid rear line out of a section of the old pipe work. Obviously you need an end with the plastic retainer section, cut the pipe to length, slide on the screw in securing attachement from the old brake line, use a brake pipe flaring tool to flare the end, then bend to shape and fit.
Looks so much neater, same as standard non abs fitting and you've used genuine bmw parts.

 

[Buckingham]

Thanks Dr, that makes sense. I was thinking it’s something electronic that activates a pressurised system.

I’d like to understand the system more to be a able to prove it’s that 100% and then I’d be happy to remove it but it’s going to be an integral part of the pump unit so I can’t.

I still struggle to accept that the servo doesn’t start to with the front brake lever but does with the rear. Also that there was no fault codes stored. I don’t want to doubt the technicians ability to use the tool but I can’t help but wonder......

Mark


Sent from my iPhone using Tapatalk

That's because the servo has separate circuits and pumps for front and rear brakes. 4 fluid circuits in all, 2 front + 2 rear.

 

[waggy]

Hi

Completed the servo removal this weekend and all went well
@Luke
I would like to try your method of repining the cables between the servo and ECU. Can you let me know where you get the pins from please?

I can live with the 2 flashing lights on the kombi for a while and rather than split that I might try and do the rewire and buy the software and connectors.

Regards

Sent from my COL-L29 using Tapatalk

 

[Santa-2512]

Hi

Completed the servo removal this weekend and all went well
@Luke
I would like to try your method of repining the cables between the servo and ECU. Can you let me know where you get the pins from please?

I can live with the 2 flashing lights on the kombi for a while and rather than split that I might try and do the rewire and buy the software and connectors.

Regards

Sent from my COL-L29 using Tapatalk

3 clips and 4 screws if i recall to split the Kombi -

A blob of mastic and some PU foam takes about 30 mins to do

 

[Mark_C0]

Do I need to purchase the ‘ultimate’ package for MotoScan to be able to reprogram the modules to stop it looking for the ABS???

Thanks!!


Sent from my iPhone using Tapatalk

 

[DrFarkoff]

I think if you search the forum for Denzo + ABS

He did it with a Motoscan

Apologies he did the fuel strip conversion and re-pinned the wiring connector and changed the programming

BUT There is this now

https://www.ebay.co.uk/itm/EMULATOR...-1200-GS-GT-LT-RS-S-RT-ST-R-C-CL/262895740608

I quite like the idea of a flashed module But £250 is a bit steep

But does clear the lamps and remove the need for the painting LED's etc

 

[Kew]

My 2006 doing more or less the same thing

So did you not find a fix to your problem & just bypass the servo ?
Mine is doing more or less the same,pump doesn’t run when front brake is applied but the brake light works & when rear is applied the pump runs continuously & then I get the from brake working as it should.
Then some days I take her out & everything works as it should for the first 10 min & brakes stop working again!

 

[DrFarkoff]

Mark trust Me its shagged

They are a crap design there are 4 circuits 2 control 2 slave

"Usually" one of the pressure pads in the pressure cylinders quits and the system shows Pressure too high rear circuit Which is a favourite

You can't just rip it out Well you can But you MUST retain the ECU part of the ABS unit for the speedo and lighting functions repipe it as per a non servo ABS bike and paint out the ABS LEDs on the board and you have std brakes again

Chances of recovering the unit are SLIM

The Servo ABS system was a great idea But the Brake circuit fluid is supposed to be changed every year and the control circuit every other year I did this because I knew about it But I wonder how many your bike had in 16 years??

Check this out https://www.ebay.co.uk/itm/EMULATOR...-1200-GS-GT-LT-RS-S-RT-ST-R-C-CL/262895740608

 

[ioginy]

Firstly, apologies for the delay in posting this, but here is my take on removing the ABS unit (and module) from my own 2005 R1200GS. This is not a guide as such just a detail of what I have done to my own bike.

So, a quick backstory, I saw a low mileage, very nice condition BUT VERY CHEAP GS for sale earlier this year, further investigation revealed it was cheap due to it having an ABS fault. I am a Diagnostic Engineer for a well-known car manufacturer so figured I should be able to fix it myself and that the bike was worth a risk. So, I ordered the bike without seeing it and had it delivered.

My original intentions were to strip and attempt to repair the ABS pump, but the more I looked into it and found out the multitude of problems these units can have the more I edged towards removing the servo and ABS all together.

I planned to carry out the ABS pump removal as many others have and to leave the control module on the bike to keep the speedo operating, just blanking out the warning lights.

For the front brake hydraulics, I decided not to fit a fluid loop to the front brake manifold as most do. Instead opting for a Goodrich build-a-hose between the Front brake master cylinder and the bottom fork bridge clamp, I used a P-clip to secure the hose at the attachment point usually used by the manifold, which gave me a very nice hose routing. (Hopefully a picture of this is attached?)

For the rear brake hydraulics, I opted to order an original rigid hose for a NON-ABS bike from motorworks for ease and a factory look finish.

The brakes bled out easily and work very well indeed.

I then went about blanking the warning lights in the instrument cluster, however I soon realised that I would not be happy with this solution.

The reason for this was because the red LED’s for the warning triangle light take precedence over the yellow ones and due to the ABS fault on my bike the RED warning triangle was constantly illuminated, meaning I would never see the yellow triangle for faults such as bulbs or fuel level.

I then set about acquiring the wiring diagrams for both ABS and NON-ABS variants, which confirmed what I had read around the speedo being controlled by the ZFE module on NON-ABS bikes. It appeared, all that was required was to connect the rear wheel speed sensor to the ZFE and programme the bikes modules for NON-ABS. Simple!

The details of this are as below, I’ll start from the point I had already removed the ABS PUMP and module. With regards to the programming I purchased the Motoscan app and a decent Bluetooth OBD dongle with an adaptor lead, I have heard very mixed reviews about the Motoscan software, but for me it worked perfectly.

The first thing I did was to disassemble the ZFE module multiplug to identify the pin types I required for the new connections (I have managed to source the correct pins and have some spares, so if anybody requires some let me know) (picture of pins should be attached?).

Once I had the pins the wiring modification was very straight forward.

Firstly, I crimped 2 pins to around 800mm of 0.5mm2 wire each. I then fitted the pins to the ZFE module multiplug. One to PIN 13 and the other to PIN 51 (these can be identified by small numbers embossed in the plug itself)

I then ran my new wires alongside the original loom down to the vicinity of the ABS module.

Next, I cut the wires that connected the rear wheel speed sensor to the back of the now redundant ABS multiplug (PINS 6 & 8), I did this one at a time so as not to get things muddled up.

The wire that used to connect to pin 6 of the ABS module was soldered to my new wire connected to PIN 13 from the ZFE and insulated with heatshrink. The same was done to connect the second wire (previously to PIN 8 of the ABS module) to my new wire connected to PIN 51 of the ZFE.

This is all of the wiring modifications required and it would have been ample to insulate the old ABS connector and tape/cable tie it away somewhere….. I opted to remove it completely as I never have any intention of returning the bike back to ABS.

I then used the Motoscan app to recode the bike to non ABS. It is important to note that I had to recode the ZFE, ABS, Engine ECU and Instrument cluster, they all had a drop down with ABS fitted YES/NO. I found when I only coded one or two of the modules they resorted back to ABS with the next ignition cycle. I presume they do some kind of “handshake” on boot up and ABS fitted takes precedence.

Once recoded I keyed the bike on and spun the rear wheel and found the speedo to be working as hoped! I was able to un “blank” the warning lights in my instrument cluster and now all of the telltales illuminate and go off again when switching on the ignition just as a NON ABS bike would. I have since also removed the front ABS sensor and sensor ring..... I may remove the ABS disable button one day to totally finish the job!

Apologies for the rambling document and that I didn't take any (useful) pictures at the time.

Hopefully, if you have made it this far, you may have found it interesting/helpful.

If anyone has any questions or are attempting to do the same conversion to their bike and want some advice, let me know.

All the best

Sent from my SM-G965F using Tapatalk

Hey Luke
Would you happen to know the part #, Style description, or defining characteristic of the pins for the ZFE plug. Or if you have a couple left over still, how would you feel about sending some to canada?

Thanks a heap for your work on this as well. I had been hunting for ever to find this solution, and a fellow is advriders linked me to this post. Absolutely perfect.

 

[Bwells]

I've been riding my 1200GS for about 3 years with the servo removed and warning lights masked out. I'd like to rewire the rear wheels sensor to the ZFE as you did, but have been unable to source compatible ZFE connector pins (sockets). If you could provide a source/manufacturer and part number for the pins it would be a tremendous help. Thanks much.

 

[ioginy]

I've been riding my 1200GS for about 3 years with the servo removed and warning lights masked out. I'd like to rewire the rear wheels sensor to the ZFE as you did, but have been unable to source compatible ZFE connector pins (sockets). If you could provide a source/manufacturer and part number for the pins it would be a tremendous help. Thanks much.

I've been able to source some. If you DM me I can get your info and send you some.

 

[Bigjimknickers]

I think it’s disgusting that a motorcycle can have catastrophic brake failure & not get called in for a recall, the least bmw could do is sell an “upgrade” kit to remove the abs & plug in some sort of module into the pump plug to code out the faults & the pipework to make it a non abs bike.
My 05 47k has whizzy brakes & it makes me pretty nervous reading about this potential fault!

 

[armichelsen]

Hello all,

Firstly, I have taken a look through the many posts about the ABS system using the search feature and i cant find any answers the same as mine, also ive asked in the FB group and Google cant match my fault so here goes......

Thank you in advance in reading this, Ive joined the forum today after a few recommendations from the FB GS group.

For my history, im a very competent car mechanic with comprehensive mechanical/electrical and diagnostic skills so I will (hopefully) understand your suggestions etc for this post

My bike is a 2004 R1200GS, 25000 miles with servo ABS. I brought it last year, rode it 350 miles home and parked it up, thats where it stayed until this Virus put us on lockdown so I decided I will dedicate the time to it and get it in operation again for the good weather. The battery (15 months old) was completely flat obviously so i put it on a recondition cycle on my c-tek charger and within a day it was ready to go.
The bike cranked over perfectly for a few seconds and sprang into life.

The ABS lights where flashing as usual until its ridden to 6mph (or whatever it is) but this time they didnt turn off so after riding it for 1 minute i returned back home to double check the obvious things. Everything looked ok, brake light works on front and rear levers but i noticed that if the bike was turned off and IGN on, i could pull the front brake lever and the servo does NOT operate but the brake light does. If I push the rear brake pedal the servo and brake light DO operate but when i release the pedal, the light goes out but the servo doesnt. The servo will run continulously until the IGN is turned off.
Once the rear brake has been pressed to activate the servo, the servo sounds perfectly normal when running and if the front or rear brakes are used, the sound of the servo changes in pitch as it always does. I disconnected the battery for a couple of hours and made sure it was fully charged once more (which it was) then connected it all back up but it was still the same.

I decided to take the bike for a little ride and see if it had any characteristics - I rode it for about 5 miles with the lights flashing and everything felt fine for the first half, I found some gravel and slammed the brakes on 1 at a time and the ABS does work for both wheels.
On the way back i noticed as i pushed either brake, the servo assistance was 'coming and going' which made for very interesting stopping distances! It sounded as if i was releasing the brake then reapplying it but i was applying a constant pressure.

Now, I have a Snap-On diagnostic tool for the cars that I work on but nothing for bikes so i called my local motorbike shop who said they do have the diagnostic tool to read the ABS on this bike and i could bring it to them to read the codes for me. (as i always tell everyone - "plug in>diagnose>repair") Their diagnostic scanner said there was no codes stored. This completely baffles me as if theres a light flashing and the system is obviously not working properly, there should be a code to tell you whats wrong with it

They suggested to me to bleed the brake system through as the have seen this kind of issue with Ducati's and a bleed sorts it out so I brought it home, took the tank off and bled the system (including the 6 nipples on the abs unit) as per a workshop manual i found online. Nope, still the same

I then got a wiring diagram for the bike and started investigating the system manually, the brake levers are connected to the ZFE control module and the wiring is fine to and from them with everything working as it should, the fluid level switches on te abs pump are connected to the ABS control module, they are working ok. The wheel speed sensors obviously work as the ABS works from my earlier test ride. All the powers and Grounds are ok, I am getting CAN signal to the ZFE and ABS modules, the CAN is 60 ohms, the CAN voltages are ok and i put my oscilloscope on the CAN and the signals look ok also.

At this point im running out of ideas

So now my thoughts are -
* Its a servo/electronic issue (not ABS as this works although i know its the same system)
* The servo does not operate initially from the front brake lever but the signals are ok to the ZFE module
* The servo does operate initially from the rear brake lever and the signals are ok to the ZFE module
* fluids have been completely changed with fresh DOT 4 including all 8 bleed nipples, as per the service manual i downloaded.
* The brake lever signals go to the ZFE module then the servo operates via CAN instruction

Im wondering if the bike shop only scanned the ABS module but theres an existing code in the ZFE which may not have been scanned? If the ZFE is having a tantrum due to the voltage decaying to 0 as its been left for so long then may not have liked the bike being charged up (I did not disconnect the battery when charging, i know i should have)

I do not want to jump in and remove the ABS system, im looking for definite answer what the fault is, if its the servo/abs unit itself then i will have to remove it or get it repaired but its the diagnostics im struggling with and finding out whats wrong with it.

My Snap-On diagnostics tool will read all BMW cars, I have ordered a lead (1 weeks away) to allow my 16 pin OBD connector to plug into the motorbike but i dont know if it will be able to read it or not. It depends on if BMW gave motorbike and car ABS systems the same CAN address and if i can pull the codes from it once ive found the correct protocol.


I would really appreciate for someone to give me some more things to check / suggestions / experience etc as to if you have heard of this fault before? and where to proceed to next? I really dont want to rip it out until its confirmed as 'dead'. Bikes location is Clacton on sea, Essex.

Thank you all so much for your time in reading this (if youve got this far). I'll post a few pictures below of what ive done/ found etc

Kindest regards & stay safe!

Mark

Hi Marc. I got the exact same symptoms on my 2004 R1200GS. Did you solve the issue and how? BR. Anders.

 

[DrFarkoff]

Hi Marc. I got the exact same symptoms on my 2004 R1200GS. Did you solve the issue and how? BR. Anders.

Simple answer that everyone has known since about 3 years after these things came out

the Servo ABS systems are complete schite!!! It is not IF it will fail .........................it is WHEN it will fail

So Basically no matter what fine words and straws you are grasping at ....... Its FUCKED!!!

Pull it out (Servo-Ectomy!) OR spend £1200 and get a new ABS system and this time follow the service schedule implicitly!

Wheel circuits Annually

Control Circuits Bi-annually

99.9% of owners probably did not know that

 

[DrFarkoff]

I do not want to jump in and remove the ABS system, im looking for definite answer what the fault is, if its the servo/abs unit itself then i will have to remove it or get it repaired but its the diagnostics im struggling with and finding out whats wrong with it.

You and a hundred others See my answer down below !!

Honestly The royal "WE" on here have seen and heard all this Maybe??? What if I?? Etc etc etc for years

Short Answer ?? Its Fucked

It is WHEN the system will fail and you Really Do NOT want to only have residual braking when you need Full power brakes!

My Answer above gives you options

 

[armichelsen]

Simple answer that everyone has known since about 3 years after these things came out

the Servo ABS systems are complete schite!!! It is not IF it will fail .........................it is WHEN it will fail

So Basically no matter what fine words and straws you are grasping at ....... Its FUCKED!!!

Pull it out (Servo-Ectomy!) OR spend £1200 and get a new ABS system and this time follow the service schedule implicitly!

Wheel circuits Annually

Control Circuits Bi-annually

99.9% of owners probably did not know that

Thanks for the thruthful answer.

The 2007+ conti ABS system does not adapt directly. How do you work around that?