Have a car getting selector error 72 at times. Getting other errors on CLC. Unit will run up about 2' and just slow down then speed back up make a bad landing at the 2nd floor. It is a 2 stop with dual jacks thought it was the sensor, but that didn't pan out? I have replaced the selector board, main and aux. sensor board. Problem still exists, also checked the switch tree.....Thinking of replacing the CLC ? Oh does the same thing in the down direction? Any Ideas? And every 20 or so runs it will make a few normal landings?

Check the directionals limit. Sounds like it could be seeing both in the same state.

yes maybe stuck in the directional limit switch tree

Did you check the back card and the orientation of the two magnets?

Well, after talking to several mechanics on the phone. And conversing back and forth! I was losing the FST relay contacts on the relay board. It sure gave me a bunch of crazy errors!

Good find, thanks for the update...