My ABS fault has cleared. Last fall my 92 K75S (77K miles) threw an ABS fault while tooling along the highway. I taped over it and kept going. Next day I was near Heid's in the Daks so I stopped to see what the fault code was. Rear modulator. "Want us to change it out?" $$$$$$$$$$$$$$ "No thanks, I'll just ride it home."
Since I do my own wrenching I took the time to eliminate other possibilities first. Even used ABS1 modulators were expensive and gave no assurance that they would last even a day. Big gamble and NOS modulators just take my breath away. So, over the winter I've been going thru the bike working on connectors and connections hoping for a Hail Mary repair before I dropped the big bucks and opened the brake system.
I cleaned/worked the ABS brain connector, the relays, all the blue plugs and any other connectors I could find. Even if it was not ABS related it had been a long time since original assembly. Inch by inch. Last Friday I removed the right 'battery cover' and cleaned the 5 connectors there. CRC electrical or electronics cleaner seems to work nicely but it really helps to use a pipe cleaner as well (remember pipe cleaners????). Wet the pipe cleaner with the CRC stuff and GENTLY swap out the sockets and wipe down the pins. Look at the munge on the end of the pipe cleaner. Did a long ABS reset (75 seconds just for good measure - thanks Don) and buttoned all that back up.
Started the bike and, for the first time in 6 months, got normal ABS lamps. Tested both brakes and got normal lamps. Rolled down the driveway and the lamps cleared. Woooooo. Hail Mary worked again. Rode 60 miles over back roads and potholes and got no new faults.
An owner/mechanic will take the time to work thru the bike before throwing big bucks at a problem. The BMW Certified Technician will normally not have the time so will just start replacing parts. That could have cost me a fortune.