Not another Boring Servo ABS Question....

[Rotaxmaxracer]

Sorry guys, but at risk of sending you all too sleep I have a question please on my 2006 Servo/ABS GS12. Recently kept having the rear brake light stay on (thereby disabling the servo). Took it to a local BMW specialist who ran a diagnostic on it and determined a fault on the front brake light switch.

He replaced the switch (which cured the fault) and the codes - but did say that it has originally indicated a over pressure fault code on the rear brake...so the problem MAY come back.

Didn't even get home until the problem remanifested itself (£190 lighter in pocket) and so I am guessing this is an ABS problem. I have read up on the Servoectomy articles here which remains an option, but was just exploring alternatives when I came across this company on the forum.

Can anyone tell me if this is likely to be the part causing the issue as I don't want to send this away if on the wrong track - unsure if it's the ECU/Pump or the modulator as I have heard reference to both?

http://www.ecutesting.com/catalogue/product/bmw_r1200_abs_pump__ecumodule_combined_amc108473.html

Have checked and lubed rear light connection and rear brake light switch seems to be working well?

Thanks in advance

 

[Steptoe]

Sorry guys, but at risk of sending you all too sleep I have a question please on my 2006 Servo/ABS GS12. Recently kept having the rear brake light stay on (thereby disabling the servo). Took it to a local BMW specialist who ran a diagnostic on it and determined a fault on the front brake light switch.

He replaced the switch (which cured the fault) and the codes - but did say that it has originally indicated a over pressure fault code on the rear brake...so the problem MAY come back.

Didn't even get home until the problem remanifested itself (£190 lighter in pocket) and so I am guessing this is an ABS problem. I have read up on the Servoectomy articles here which remains an option, but was just exploring alternatives when I came across this company on the forum.

Can anyone tell me if this is likely to be the part causing the issue as I don't want to send this away if on the wrong track - unsure if it's the ECU/Pump or the modulator as I have heard reference to both?

http://www.ecutesting.com/catalogue/product/bmw_r1200_abs_pump__ecumodule_combined_amc108473.html

Have checked and lubed rear light connection and rear brake light switch seems to be working well?

Thanks in advance

You have a different abs modulator... You have a servo/abs modulator. The company you've posted a link to only work on the later models ABS (non servo) modulator.

 

[Bendy toy]

Is it possible for seizing brake caliper pistons to cause an over pressure error at the servo? Now could be a good time anyway if the caliper has not been recently stripped (pistons and seals out) and cleaned.

 

[Rotaxmaxracer]

Thanks a bunch Steptoe...saved me time and embarrassment there ;-)

 

[Rotaxmaxracer]

Cheers Bendy toy, definitely worth a look. I also wondered if the error had previously been triggered by the fact that my rear pads were extremely low - recently replaced? The front pads are also quite low, so I am told it may be worth replacing them also before spending out for a servoectomy?

 

[Pukmeister]

Cheers Bendy toy, definitely worth a look. I also wondered if the error had previously been triggered by the fact that my rear pads were extremely low - recently replaced? The front pads are also quite low, so I am told it may be worth replacing them also before spending out for a servoectomy?

If you have had a brake fluid change by the dealers prior to fitting your new pads, it is possible that the Servo unit internal reservoirs ( NOT the handlebar/pedal reservoirs) are now overfilled due to the fluid displaced by the thicker new pads. If so, this could be the cause of your over pressure fault. The only way to be sure is to remove the petrol tank and unscrew the reservoir vent/fillers and check levels/draw off some fluid.

 

[Rotaxmaxracer]

Thanks Pukmeister, thats definitely worth a go before going to the trouble and expense of a Servoectomy I think.

 

[Steptoe]

If you have had a brake fluid change by the dealers prior to fitting your new pads, it is possible that the Servo unit internal reservoirs ( NOT the handlebar/pedal reservoirs) are now overfilled due to the fluid displaced by the thicker new pads. If so, this could be the cause of your over pressure fault. The only way to be sure is to remove the petrol tank and unscrew the reservoir vent/fillers and check levels/draw off some fluid.

No need to worry about being overfilled, it's not possible.
There's an overflow for if the fluid level is too high. The overflow pipe exits by the R/H footrest.

 

[kevingambrell]

No need to worry about being overfilled, it's not possible.
There's an overflow for if the fluid level is too high. The overflow pipe exits by the R/H footrest.

Thank you, you just answered a question I had wanted to ask.

 

[Pukmeister]

No need to worry about being overfilled, it's not possible.
There's an overflow for if the fluid level is too high. The overflow pipe exits by the R/H footrest.

Bugger, that's that theory out the window then.

Maybe doing a fluid change on the ABS Servo unit might flush things through and cure the fault ?

 

[Bendy toy]

I would rebuild all three brakes, remove pistons, clean the seals and rebuild. The servo might not behave any better but you'll know the brakes are not adding to any servo issues.

 

[Michal Fonts]

Rear brake light switch, located behind the lever pivot.
It will be corroded, fit a new one. Thats how I fixed the exact same problem on mine.