Integral ABS Gen. 2 fix - my take

There are quite a few threads/utube videos of how to fix the Integral ABS Gen. 2; that is how I got to try and fix one on a friend's 1200GS, 2007.

The bike is like brand new, just 13k kms on it. Weird how the ABS module started to go bad at such a low mileage.

I noticed that the unit can also be found on the VAG cars, I have seen it on WV Golf, my Audi, even some BMW cars have it. the units are not all exactly the same, there are more lines on the car units - 6 lines and the bike only has 4 lines. Also, the motor housing somehow differs, it is a little more compact on the bike unit, given the limited space; also, the car unit motor shaft is slightly larger in diameter than the bike one. I know about these differences because I bought a cheap Golf MK3 unit after fixing the BMW bike one, for comparison reasons.

 

 

Also, I think it is impressive how the engineers came up with this simple and light solution, compared to the previous units that weight so much more. Also, manufacturing these units would be so scalable since many of the parts would fit on so many cars and bikes, so theoretically, the manufacturing price should be lower. The one that gets fitted to the BMW bikes is made by ATE - they have so nice products: car rotor discs, brakes, etc. They seem to be on the market for 100+ years!

 

Back to the bikes...

 

The one I was working on showed these two errors:

 

2 fault codes found:

 

24048 Pump motor defective

The fault is currently present.

24049 Power Supply to Pump motor faulty

The fault is currently present.

 

... on the GS911 unit. The messages were written in red, so the problem was still there.

 

In order to not make a mess, you would first have to drain the brake fluid on both front and rear circuits. Obviously, the bike's fairing and fuel tank need to come off.

Then, cut all the plastic retainers that keep the abs harness in place. Get the abs connector off the unit by pulling the tab upwards, while the connector slides out of the unit. Information about getting the abs unit out from the bike can be found here -

 

The video says that you have to drill two holes in the housing at 8 mm center distance from the tabs. That is wrong and it will make you break the holding tabs. Drill two 3 mm holes at 4 mm distance from the tabs and you will not destroy the tabs

 

For taking the brake lines off the bike, cut a 12 mm round wrench so that you can get it trough the brake line, so that you have as many resting points on it as possible. Do not even try to undo the lines using a regular wrench that only has two contact points on the brake nipple!

 

 

The above video also shows how to get the motor apart from the unit, using a chisel to cut the retaining tabs. Don't worry doing so, since when you put it back, you will have to weld it back, in order to be sure the motor stays secured to the unit.

 

This is how the motor looks when taken apart from the module:

 

 

This is a 12 V motor, the terminals are for + and -, changing the way you power it will decide if it spins CW or CCW.

Also, note how the spindle is eccentric relative to the middle of the housing, that is the interesting part on how this works. The spindle tip gets inserted inside a needle bearing that sits inside a bushing, in the aluminum body. That bushings presses alternatively on two valves inside the module, making the ABS work.

 

 

You can see the valves in the above picture, sitting at 2 and 7 o'clock. Ideally, the bushing has to stay inside the aluminum block when you get the motor outside. It can happen that it stays on the motor spindle and the valves will come unloose from their place - ask how I know.

If that is the case, you can use two feeler gauges to press the bushing back in and also press the valves back in their spot. Most probably that won't be the case, but if it does happen, you'll know how to fix it.

 

So... once the motor is out, it is time to fix it. As you might know, the problem is with the brushes, not making contact on the rotor commutator. Since the bike had such a low mileage, the brushes couldn't be worn. Also, this is not a motor that would run at all times so that the brushes get hot and come unloose, like the one on a car ventilation system could.

The motor I had would keep the brushes locked into position, just cleaning the brushes recess did not help making them loose and touching the commutator. I had to take the plastic cap off in order to fix this, but the plastic cap that holds the bushings is held in place by the bearing that sits in the aluminum housing.

 

The bearing code is 6000C, one side has a plastic protection and the other one has a metal seal. You will have to buy a new one, get the 6000Z one with double sided metal seal.

 

There is no way of getting the bearing off the spindle but cutting it. Take your time, cut the outer side of the bearing, get the balls off and then cut the inner side of the bearing, don't worry if you slightly touch the spindle.

 

Once the bearing is off the spindle, this is how the brushes holder looks:

 

 

You can see that the brushes are as new, almost no wear on them and the springs that are supposed to push them towards the rotor do not have enough force to do the job.

Usually, you would have to take the brushes off, peel them on the side and when mounting them back, they should slide just fine. But these brushes cannot be taken off their mounts...

 

 

 

My idea was to cut the part where the wire stops the brush in order to enlarge the recess and make the brush move freely inside it.

 

 

 

This way, I would still have the functionality of the brush wire stopping and I was able to enlarge the recess using a thin cardboard cutter just enough to make the brushes move freely in there.

After I have mounted the motor, I have applied 12 V from a battery to it, to make sure it works just fine. Do not run it for a long period of time as it will heat. It works for small periods of time anyway when the ABS kicks in during braking. I ran it continuously because I wanted to make sure that the brushes touch the rotor as they should.

 

The rotor had some dirt on it and since I had the lathe without any work on it, I decided to clean it.

 

 

 

 

The motor housing has four magnets and two springs that keeps the magnets in place. It can happen that the magnets move while you take the rotor outside the housing, I checked mine and took the springs apart, used some compressed air and after mounting them back, I used the glue gun to make them stick inside for good.

 

 

Mounting was in revers order of how I took it apart. After putting the brushes cap over the rotr, I pressed the new bearing on and pushed the whole assembly in the magnet housing.

 

Like I said, after fitting the motor to the unit, I went to a local welder shop and put some aluminum weld over the motor mounting tabs, in order to make sure it stays in there and not drop off. The rubber seal between the brushes cap and the motor housing did not suffer because of the welding heat.

 

After fitting the module to the bike, I flushed new brake fluid and I have used the diagnose unit and ran the available ABS tests. All seemed fine and I took the bike for a ride. The abs light on the dash went off and it kicked in when needed, basically it worked as it should.

 

I have tried fixing this because another unit would cost ~ 400 eur around here. There is also the risk of getting a replacement/donor unit and have it's brushes locked as well.

Since these run for hundreds of thousands of kilometers on cars, I think they should work just as fine on the bikes.

 

Dan.

Great write-up! Thanks!!!

Hey Dan your website link is broken.

Seems to work now, thanks!

One thing I forgot to mention, might be useful.

Since I have a GS911 diagnose unit, in order to verify my work, when the unit was repaired, I connected it to the bike's harness and I was able to perform motor related tests via the diagnose.

 

I was able to spin the motor, that was good enough test for me.

 

Dan.

The GS911 also shows pressure in the front/rear brake lines.

Pump the front and you see the rear pressure up as well.

I am going to have to get a GS911 at some point.

I don't know how many things it can diagnose? The brakes?

The engine fueling system? The electrical components and cruise control? Re-sets, like tire pressure sensors and service lights?

Thanks, Mark

Also heard to watch out for Chinese knock-offs, are they junk ?

I got the low volts alarm again this week.

Already pulled it out once and fixed it.

Wonder what I missed?

Bugger.

HOW did you fix it? Did you cut the brush holders like I did?

I got the same result you got. Just cleaning the brush holders won't do, you have to cut that recess in order for the brushes to slide freely inside them.

 

Dan.

I am going to have to get a GS911 at some point.

I don't know how many things it can diagnose? The brakes?

The engine fueling system? The electrical components and cruise control? Re-sets, like tire pressure sensors and service lights?

Thanks, Mark

Also heard to watch out for Chinese knock-offs, are they junk ?

 

If you are a do-it-yourself type, the GS911 is money well-spent. By all means, get the real thing and don't waste your money on an unsupported and questionable device. You are close to Ted Porter's BeemerShop. I've purchased two from him. I'd ride over and check it out.

+1 on the Gs911 diagnose. In case you do not want to spend that much, search for the old yellow one, I guess there are owners looking to sell the old one and get the new one. I did just that.

 

Also, it proved to be perfect today to troubleshoot a Husqvarna Strada.

 

Dan.

HOW did you fix it? Did you cut the brush holders like I did?

I got the same result you got. Just cleaning the brush holders won't do, you have to cut that recess in order for the brushes to slide freely inside them.

 

Dan.

 

I just flushed them with a can of contact cleaner and it all seemed good to go, 3 months ago anyway.

I have a feeling I didn't flush the Magnet area. Just waiting for an empty fuel tank and time to get back at it.

Work and Life are getting in the way at the moment

 

How did you cut the bearing off? Dremel?

 

You should just need to put an ohms meter across the motor contacts.

Open circuit = stuffed, short circuit = good.

 

Also I still have a set of R1100 Throttle body parts you sent me in September 2013 and arrived in March 2014.

You replaced them at the time. Do you want them back? Unopened, still in the padded bag

I am going to have to get a GS911 at some point.

I don't know how many things it can diagnose? The brakes?

The engine fueling system? The electrical components and cruise control? Re-sets, like tire pressure sensors and service lights?

Thanks, Mark

Also heard to watch out for Chinese knock-offs, are they junk ?

 

I have a GS911 (unlimited) available for borrowing, depending on where you are in Norcal.

Edited November 30, 2016 by NickInSac

I would be interested in borrowing the GS911 from you. I'm in Vallejo.

 

I have the ABS fault and need to find time to take apart the bike and do the work.

The ABS unit failed 1 week after the shop did the brake flush, and I think they did not do a good job, but they are also not taking responsibility

for the failure.

Just my personal opinion but I wouldn't connect any electrical component from China that's known to be pirated just to save money.

Any money saved is potentially wasted if the cheap Chinese crap fries your ECU.