All this season I have had issues with my '01 ABS II going failed with a '016 Piston Fault'. I have 95K on the ODO and I have owned the bike for the last 9 years. I installed the pin 21 wire on the ABS cable from a previous thread and was able to reset the fault and used the bike for most of the summer with no issues. After about 3K miles (two months), from the initial reset, I had a fault again while on way to CCR in Boise. My riding partner to CCR, billd, brought along his GS 911 and we were able to reset the fault numerous times but it would always work first thing in the morning but fail on the next startup. I'm not sure if it was startup diagnostic or runtime failure, however I noticed the wigwag pretty early after getting underway from a restart, never after the first run in the morning after a fault reset at end of day..
I decided to attempt the procedure to clean the pistons in the ABS unit using the reset procedure from here
. I made the 22 MM tool and proceeded to do the repair. I took a lot of pictures so I could remember all the details, should something go wrong. Lot of particles in both the front and back circuits but I could not find any dirty smudges on the pistons or see anything out of order in the cylinders accept the back circuit had trash at the bottom of the cylinder for the ABS piston.
After completing the reconnect of all the parts I was able to reset the diagnostic error (seven pulses) on pin 2 in the Motronic connector, which I had not
successfully done over the last month since returning from Boise. I tried multiple times on multiple occasions. I was very happy to say the least.
I took the LT out for a test ride and I was able to get the rear circuit to pulse and activate the ABS however since it was dark I did not want to try the front circuit for obvious reasons. I rode back home and decided I would turn off the LT and restart and try another ride off. I turned on the key and the startup diagnostic gave me correct simultaneous flash. I let the clutch out and within 3 feet I heard a clunk and I got wigwag ABS lights. I reset the fault again and got the normal simultaneous flash of the ABS warning light. This time I did not touch the brakes before I restarted any
forward motion, before or after, the initial diagnostic. Again within three feet I got the clunk and the wigwag.
I again reset the wigwag and this time I will wait for morning to try to make it fail looking carefully at the failure points. I will also try to attempt to use the front ABS circuit if I can find a good spot to do it safely.
Since I don't have a GS 911 to get the exact fault I'm looking for a guess form anyone that has had a similar problem (clunk in three feet and wigwag indication) or someone with knowledge of what is done within the first few feet. My battery is fine, I did new brake lines in early 2010, I have changed the brake fluid numerous times over the years to avoid this sort of thing. However, I have not looked at the gaps on the sensors, I will do that tomorrow as I'm done for the night. The fact that it works for many miles on initial startup would lead me to believe that they are good but warm up could be causing the gap to change and they might tighten the pulse specs during initial startup runtime. The wheel does get warm.
This appears to me to be a symptom change because I could not reset the fault for the last two months. I may
have had two