K75rt 92 ABS

[fbmartin455]

Have a problem with ABS lights flashing contiuously after startup. Have had then reset but they continue to flash. Have had the sensors checked and rechecked and they are fine. THe antilock function still works just the darn lights won't shut off. Any suggestions on how to get the lights off?

[lorazepam]

sounds like a low battery problem, also check to see if your taillight and brake lights are good.

[YB in IN]

Originally posted by bmwman
Any suggestions on how to get the lights off?

Black electrical tape should do the trick.

[deilenberger]

Originally posted by bmwman
Have a problem with ABS lights flashing contiuously after startup. Have had then reset but they continue to flash. Have had the sensors checked and rechecked and they are fine. THe antilock function still works just the darn lights won't shut off. Any suggestions on how to get the lights off?

How have you checked the antilock function?

You may want to read out the error codes the ABS brain has stored. Normally the low battery voltage error will reset itself if you ride the bike a bit and then stop and restart it.

There are some indications I've seen that persistant low battery voltage may eventually cause a failure of the ABS-CPU.

You can find lots of info on ABS and how to read out the codes on the IBMWR website - plus how to reset it yourself. Look under the K-tech-FAQ pages (search for ABS).

BTW - I have seen on ocassion where the ABS brain requires a "LONG RESET" - which instead of the 10-15 second one, it requires at least a full minute to reset. This is not documented in any documentation for the ABS brain, but it did come from a reliable source.

[K12RS03]

'92 and (my) '93 K75 ABS control units ("brain") were particularly badly designed. Reading the code will probably give you a fault code 7 "ABS control unit". Start looking for a '94 or newer unit. Send me an email or message and I'll email you the procedure to read the code.

[deilenberger]

Originally posted by K12RS03

'92 and (my) '93 K75 ABS control units ("brain") were particularly badly designed. Reading the code will probably give you a fault code 7 "ABS control unit". Start looking for a '94 or newer unit. Send me an email or message and I'll email you the procedure to read the code.

It's probably quicker to go to the IBMWR website and look under K-tech pages. The codes are there, the reset proceedure is there, and how to read the codes is there.

There is also extended diagnostic troubleshooting courtesy of Brian Curry. This can be found at:
http://www.ibmwr.org/ktech/abs-diagnostics.shtml

If you have a code 7 - in about 50% of the cases the ABS brain can be saved. There is an undocumented LONG reset that can be done. Follow the instructions on the IBMWR K tech pages, but use 1 minute for the reset time. If this doesn't work - try 2 minutes.

If neither of these work - there is a good chance the brain has gone south. It appears the going south *may* be related to low battery voltage, so this IS something to avoid with any ABS-1 equipped K bikes.

K12RS03: There are two versions of the ABS-1 brain.. is this what you're referring to in the year to look for?

Here is the page to start at:

http://www.ibmwr.org/ktech.shtml

Look under the ABS section - lots of info there.

Best,

[K12RS03]

I don't have the part numbers for old/new units. Only know that lots of '92 and '93 K75's were problematic when I first had my failure and went looking for a replacement. Resetting was required so often that I put in a switch. Eventually it wouldn't reset.

If the bike has started acting up, I'd start looking. I wouldn't hold out too much hope. After buying a '95 unit I also bought a 'dry cell' battery. Could be that this has saved the newer control - hard to tell. Certainly BMW won't tell you what's up with them.

Also if the lights are flashing all the time I would not trust that the ABS is working - in fact it most definitely is NOT.