This is what is going on this unit. In the up direction and only in the up. The 4th landing and the only landing the car washes out levels back into the fourth floor. Fault code im getting is aways the same 171 18. I know what you are thinking im clipping a lock. That was my first instinct. So I went thru all the locks, adjusted a couple, and checked my clearances. I got clearance for days. So anyway I to go run the car and no cha I jumped out the entire dg/cg circuit. Car is still doing it. I went thru the ST circuit. Replaced all relays. I set my meter up on ST when the car does gn it the voltage on ST goes from 110 down to 89. STA stays at 110v. On the print looking at the ST circuit the only different is U contact n0 9\5 and D contacts no 9/5.

I went to the up and down circuit. I transferred all the up components to the down one at a time make a run. Transferred all of the relays no chance.

sbr, you should have over 120 vac to start with, 125 is a good level. I would change taps on the L2A circuit to get my voltage up. You are throwing an error in leveling. Are you recording an error in the Drive Log? what about the RL1 nc contact that parallels the nc leveling contacts and the DGR contacts, if you put a meter at sp2,do you lose voltage also? you may want to go through and check and tighten connections, and also check input and output pin connections. The whole terminal can get loose on these.

Analog drive, so I cannot see any faults thru the tool. It not showing any faults drive faults from the LEDs. It does it when I'm running past the 4th floor. That's why I don't get the 7 cause I shouldn't be in that part of the curve. I went thru all the connections. I'll be back on it Monday I'll put
Check those other suggestions. Thanks

Just one more thought. Is it possible that the vane reader may not be hitting the holes correctly in the up direction, and tries a late slow down at the 4th floor?

If it's an Allen Bradley drive, check drive power supply