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Discussion Starter · #1 ·
This bike has 80k miles and owner has never changed brake fluid since he purchased it 2 years ago. ABS light is flashing fast and the triangle light is on constant. Is the ABS pump caput?
 

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Discussion Starter · #2 ·
Well there has been numerous posts on this so a little research has avoided a repeat of what has already been discussed.

I purchased the bike thinking it would be a good project to work on and learn from so I will keep you posted.
 

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Yes, a little research as to what others have done with the same problem, once you have done those checks yourself w/o fixing your problem, then post, telling us all you have done.

First, find the chart that shows what the flashing lights mean.

Do you hear the servo motor run when you apply the handbrake?
Do you hear the servo motor run when you apply the footbrake?
How worn are the pads? Worn pads will cause a drop in fluid in the reservoir and cause a wig-wag.
Got to get to the unit to top it off anyway, might as well do a flush while you are there.
 

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Discussion Starter · #4 ·
Yes, a little research as to what others have done with the same problem, once you have done those checks yourself w/o fixing your problem, then post, telling us all you have done.

First, find the chart that shows what the flashing lights mean.

Do you hear the servo motor run when you apply the handbrake?
Do you hear the servo motor run when you apply the footbrake?
How worn are the pads? Worn pads will cause a drop in fluid in the reservoir and cause a wig-wag.
Got to get to the unit to top it off anyway, might as well do a flush while you are there.
Thanks Kim. I’m in possession of the bike now and yes, the servo motor runs when either the front or the rear brake is applied BUT I also here it, although not as loud, constantly indicating to me that a release valve is stuck.

I also have been informed that the dealer recently flushed the system in hopes of alleviating the fault but to no avail.

I connected a GS911 but it is not recognizing the ABS saying there is no signal from the controller.

I will report back as I dig deeper...
 

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Make sure than when you turn on the bike the brakes are not pressed or a brake switch is not stuck on.
That keeps the abs module from completing self diagnostics.
And that all brake lights are functional.


Sent from my iPhone using Tapatalk
 

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Discussion Starter · #6 ·
Make sure than when you turn on the bike the brakes are not pressed or a brake switch is not stuck on.
That keeps the abs module from completing self diagnostics.
And that all brake lights are functional.


Sent from my iPhone using Tapatalk
Will do, thanks.
 

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Discussion Starter · #7 ·
So an update is warranted... the bike does smoke although PO says it never used oil, and there is a lot of carbon buildup at the exhaust pipe. GS911 says TBPS are not in sync so I’m wondering if all this means it needs an oxygen sensor.

With regard to the ABS module, has anyone ever removed the pressure relief valve without removing the module? If so, how do you get an open end wrench on that??
 

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I have removed them but you almost have to use a socket and you need to rotate the nearby exit port to get clearance. I want to say it is 22 mm. But I may be wrong.
 

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Discussion Starter · #9 ·
I have removed them but you almost have to use a socket and you need to rotate the nearby exit port to get clearance. I want to say it is 22 mm. But I may be wrong.
Thanks John, i will try the socket but it looks like I need to remove the battery to get access with an open ended (don’t have big enough socket). In bleeding the brakes, the fluid was very dark so not sure when they were done last, however, I cannot get the pump to push fluid to the rear Caliper. Is this a clear sign of that pressure relief valve being stuck?
 

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Discussion Starter · #10 ·
I have removed them but you almost have to use a socket and you need to rotate the nearby exit port to get clearance. I want to say it is 22 mm. But I may be wrong.
The closest I have to fit is 1-1/16” so it must be a 26 or 27 mm deep socket as the wrench just does not grab enough meat to turn it.

I guess it’s worth a shot to see if the rest pressure relief valve is indeed the issue as I would like to avoid having to remove the module all together unless I decide to extricate and eliminate. The fact that I hear the module working, even if I do not apply brakes, and since it cannot push fluid on that circuit makes me believe that the rear release valve is the issue.
 

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No a stuck pressure relief valve will throw a "pressure too high" fault in the circuit. I don't have it on my diagram but I think the relief valve is between the pressure transducer and the reservoir. So if it was stuck you would still have fluid at the caliper.

If you cannot get fluid to pass out of the rear caliper there is a blockage in there some where or the "ball valve" is not closing the circuit. Might be worth it to pull the output port off and check the filter screen. Remove the clip and pop the line off then you can unscrew it.

Here is a diagram of the system:
 

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So an update is warranted... the bike does smoke although PO says it never used oil, and there is a lot of carbon buildup at the exhaust pipe. GS911 says TBPS are not in sync so I’m wondering if all this means it needs an oxygen sensor.



With regard to the ABS module, has anyone ever removed the pressure relief valve without removing the module? If so, how do you get an open end wrench on that??


When left on the side stand oil pools on the cylinders. And it burns when turned on. Even on the center stand smokes a little. On the side stand a lot. But mine does not use oil.
The oil burn lasts about a minute.


Sent from my iPhone using Tapatalk
 

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Discussion Starter · #13 ·
No a stuck pressure relief valve will throw a "pressure too high" fault in the circuit. I don't have it on my diagram but I think the relief valve is between the pressure transducer and the reservoir. So if it was stuck you would still have fluid at the caliper.

If you cannot get fluid to pass out of the rear caliper there is a blockage in there some where or the "ball valve" is not closing the circuit. Might be worth it to pull the output port off and check the filter screen. Remove the clip and pop the line off then you can unscrew it.

Here is a diagram of the system:
Thanks John,

I did remove the screen at the rear reservoir and surprisingly found less fluid than I expected when I syringed it out. Also saw that the rear master cylinder reservoir was low in fluid.

Not sure what clip you are referring to but I assume you mean the brake line at the rear caliper and master cylinder. Are you suspecting a failure in the rubber brake lines? Could this blockage also cause the pump noise to be on continuously but louder when you apply brakes?
 

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Discussion Starter · #14 ·
I forgot to mention that the center stand does not move at all but you can hear the motor running when I try to deploy. I’ll have to get it on the bench to see how much oil is in there.
 

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OK on the center stand run it on the bench with the little 4 mm ports facing up. Open the 19 mm spigot and add 10 ml of oil at a time and then run it. Repeat until it goes full stroke.


On the brakes look at my previous picture for the part I said rotate to gain access. That is the input port and the out put port is on the other side of the reservoirs. Short one is for the rear wheel circuit and the tall one is for the front. The clip is in that little slot and once removed you can pop out the hard line and remove the port to inspect the filter screen.
 

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Discussion Starter · #16 ·
OK on the center stand run it on the bench with the little 4 mm ports facing up. Open the 19 mm spigot and add 10 ml of oil at a time and then run it. Repeat until it goes full stroke.


On the brakes look at my previous picture for the part I said rotate to gain access. That is the input port and the out put port is on the other side of the reservoirs. Short one is for the rear wheel circuit and the tall one is for the front. The clip is in that little slot and once removed you can pop out the hard line and remove the port to inspect the filter screen.
Thanks John, I will try that today as I thought you were referring to the screen inside the reservoir.
 

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Discussion Starter · #17 ·
OK on the center stand run it on the bench with the little 4 mm ports facing up. Open the 19 mm spigot and add 10 ml of oil at a time and then run it. Repeat until it goes full stroke.


On the brakes look at my previous picture for the part I said rotate to gain access. That is the input port and the out put port is on the other side of the reservoirs. Short one is for the rear wheel circuit and the tall one is for the front. The clip is in that little slot and once removed you can pop out the hard line and remove the port to inspect the filter screen.
So I was able to remove the input port and understandably saw clean fluid dripping from the line that you unclip and remove but saw no screen at this port. Was also able to blow through the valve(?) so no blockage there other than I’m not able to swallow anymore from putting brake fluid in my mouth (kidding).

Was able to remove the clip from the output port but cannot un screw that valve(?) and now have no response from the pump when rear brakes are applied but still here the constant sound from the pump.

I am thinking I will need to remove the pump after draining the system to get it on the bench. Only other thought is that the blockage could be at the rear caliper although I was not able to see fluid from the output port line. Definitely not been this far in with the brake system so anything goes.
 

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Discussion Starter · #18 ·
Some pics...
 

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Discussion Starter · #19 · (Edited)
OK on the center stand run it on the bench with the little 4 mm ports facing up. Open the 19 mm spigot and add 10 ml of oil at a time and then run it. Repeat until it goes full stroke.


On the brakes look at my previous picture for the part I said rotate to gain access. That is the input port and the out put port is on the other side of the reservoirs. Short one is for the rear wheel circuit and the tall one is for the front. The clip is in that little slot and once removed you can pop out the hard line and remove the port to inspect the filter screen.
Hey John,

I did not see a screen at the input port and cannot see access to remove the output port unless i remove the pump. Before doing so, do you think that the caliper itself has failed and creating the blockage? The rear wheel does turn freely and I believe did stop when I applied foot pedal. Now that I do not have rear brakes I believe I’m looking at a complete removal of the pump either to dismantle and get access to that port or send away for refurbishing. Your thoughts and suggestions always welcomed!
 

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You should be able to get some fluid at the calipers even if the pump is not running so I am not sure what is going on. I agree it would be hard to get the output port off with out removing the unit as it is kind of jammed up there under the frame.
 
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