I'm looking for some help understanding how to get fault code for abs1 system on a 92 K75S vin# xxxxxxxxxxx153350.

 For some back round this is a new to me bike I got late in the season last year and just could not stop myself from putting a few hundred miles on it before giving it a good going over. It is a low mileage (28,000 miles) well cared for machine. So far I have de-oxed all connectors including grounds, rad flush, all fluids (except brakes), and cleaned and lubed trans input and driveshaft splines. Because the bike is in such nice condition I would like to get the abs working and keep it in original configuration (I'm not sure how valuable abs1 is it terms of safety vs 20+ lbs of mechanicals). The battery holds 12.6 volt static charge and drops < 2 volts when cranking. 

When I turn on the ignition the abs and warning lights both flash and I can hear the relay (abs?) clicking. With an anti-log volt meter - to ground and + to center pin of abs test plug voltage goes from 12 to 2 continuously. When I hit the abs switch the lights will come on steady and the voltage on test plug will go up to 12  for 3 or 4 seconds then drop to 3,4,3,4,3,4,3,4,3,4,3 then back to 12 and the sequence will go on and on. From reading the troubleshooting guides I was expecting to see "dips" from 12 volts.

So, should I interpret this reading of 6 (small) "dips" to a faulty relay?

You would get a better/easier reading if you use a analouge meter.
And yes, you should count the dips.....so it could be code 6.

Search Tosi Tabuki...he is the ABS I guru, a lot of info on his site.
He have helped a whole lot of owners.

This may help:

https://hrsbstaff.ednet.ns.ca/bvogel/K100/download/Motronic%20Fault%20Codes.pdf

This is Tosi Tabuki's site and what he doesn't know about the ABS isn't worth knowing  http://bmwk10075abs1fix.web.fc2.com/

Thanks guys let me look into the stuff you gave me and and will post what I come up with.

Inge K.,
I stated that I used an anti-log meter when in fact I used an analouge meter. I feel like a clod being born and raised in the US and struggle with written English

caveman wrote:I stated that I used an anti-log meter when in fact I used an analouge meter.

I see the similarity now , when I did read the post I was thinking......
what kind of fancy digital instrument is a anti-log voltmeter

Sorry guys but this one is going to end in an anticlimactic manor.

On Tosi Tabuki's site (thanks Rick) "If your error is 6 and cannot reset it, Do Deoxit on both pump connector located under the petrol tank.It is blue color connector under both side of the tank."


Since I had already did that , I went ahead and cleared (reset) ECU and it worked!