Hi All

I have just had the second ABS "brain" failure in 27 months. Both went the same way as in:-

Riding along enjoying the day when the ABS light started to flash rapidly. Stop and turn off the ignition, reset and restart the bike. The ABS light goes out after a short movement and all is good with the world again until the light starts to flash rapidly again, this time with real brake failure as well. There is some residual braking but nothing that would stop you in a hurry.

Both times the bike has been put onto a dealer diagnostic machine and it indicates that the ABS unit is fried.

The first time BMW came to the party and went halves in the unit with me as the bike was 3 years out of warranty but only had 27k km on the clock. Now the second time I am fighting to have the thing replaced again.

Since the first unit went I have only done 4k km.

Has anyone else had similar problems with the ABS "brain" on a 1200 GS. The bike in question is a 2005 model but I have a 2004 model in Europe that has done considerably more km with out any issues at all.

Cheers
Marty

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whoa... that doesn't sound good... any truth to these old reports?

ABS failure causing wrecks here: BM Bikes & BM Riders Club Forum • View topic - Servo Assisted Brakes - Safety Announcement
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In recent months there has been a quadrology published (Readers Edition) about BMW Motorrad Integral-ABS (FTE automotive) in Germany. Therefore it's only of interest if you do understand German language.

1. http://www.readers-edition.de/2006/12/2 ... entechnik/
2. http://www.readers-edition.de/2007/04/0 ... rte-akten/
3. http://www.readers-edition.de/2007/04/0 ... geklagten/
4. http://www.readers-edition.de/2007/04/1 ... s-kaeufer/

However, the most popular reports about brake failures with BMW Integral-Brakes in english language may be found at the end here. This list won't stop until the company recalls the brakes and replaces them with the repaired system from Continental Teves which is available since August 2006.

Unfortunately there is one seriously injured rider and a dead rider known. First case: Claims having no brakes at all. Second case: Three fault codes and one parameter out of range was found by the experts of the prosecutor.

Dr. House

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R90S, R80G/S PD

Until a few years ago I was a test engineer on ABS on trucks. I tried a servo-assisted RT when they came out and with the brake ECU pulled would describe the residual performance as lethal. The legal requirement was set in the 1950's for vehicles with cable operated drums and my professional opinion was that this bike just about matches these. Personally I'd rip off the whole system and replace it with a non-servo set up copied from the earlier bikes or just sell it to a BMW dealer and walk away. Sorry if this sounds harsh but a blown fuse taking the brakes back to Ford Anglia performance is no good what so ever in modern traffic.

However, if neither of these is an option you need to do what BMW technicians constantly fail to, find out what causes the failures. The ECU is just like any other electronics, it's worst enemy is voltage spikes and corroded connectors. Trace the loom and clean and check every connector. The main multipin must be clean and smooth fitting, no bent pins. Downgrade the fuse that feeds it, better to blow that than the ECU. While throwing money at the main unit put a couple of new sensors and a battery on too. Never ever under any circumstances short of sitting in the middle of the desert with no water jump start one of these bikes or use welding equipment. Get an auto electrician to do an electronic trace of the regulator output, anything over 15 volts and you need that sorted.

In ten years of sorting the worse sort of warranty claims from two big UK truck makers and one well known 4x4 company I came across one ECU that had failed due to something other than external items. The suppliers can make a good ECU, the problem will be IMHO in BMW's design process (they need to retire a lot of old guys and get some replacements in from Japan not the car division, but that's OT and based on a couple of very brief encounters) . A 10p connector in a stupid place or with short cables or bad earth is most likely the cause of wrecking thousands in electronics.

Andy

Thanks for the reply Andy. At the moment I would like to rip the thing off as well!

I did the wiring checks as a matter of course when the first one went as it is the first thing I would do in my normal job (Electrician) but its worth a look again I'm sure. The dealer also told me that they checked that the first time but I have my doubts as they were a dedicated car dealer back then.

I just have to wait for BMW to get back to me now that the Easter public holidays are over and see what they will do.

Cheers
Marty

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Well 4 weeks after the event and I have the bike back. It took that long as there were no ABS units in Australia. Not sure they looked too hard but have to go with it anyway. The dealer tells me that they replaced the pressure modulator pump and the ECU. Changed it to a newer model/type as the previous units had a tendency to fail. Thats nice to know when you live in a hilly twisty area!

Anyway the lot was changed under parts warranty so not too painful.

Just have to hope that it doesnt happen again.

Marty

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This screams "software update".

BMW (and another famous German maker of 4 and more wheeled vehicles) always seemed to link quality with tight numbers in my experience. It's a good plan (for them) to have vehicles call into the dealers whenever the battery voltage drops below 11.5 or some other minor issue brings the ABS warning light on. A quick 40-quid go on the diagnostic machine a charged battery and the owner of a fifty grand car is slightly miffed (but often very relieved) but that's it. When they set the number at 11.99 volts thinking there'll be more 40-quids they end up changing it later. Apply this to a fault that makes the system shut down and it's plain bad engineering.

Glad it's sorted.

Andy

Isnt the big BMW GS famous for electrical problems scince this happened while Charly Boorman and Erwan Mac Gregory where making there film "Long way round" as well???

I think they fried electronics while welding the bike.