have 3 cars, was getting complaint of doors closing on people, and not reopening.
mechanic swapped out the imotion2 door board, since it was intermittent, but same complaint, one persons hand was bruised pretty good. any way i showed up to assist and cleared all faults and started running car. when the problem happened the car answered the car call, opened the doors about 3./4 fully open and closed immediately with no door protection, i.e. detector edge would not reopen door, it then continued on as if nothing happened. it would run another 30-60 min and happen again. controller logged a G21 fault. drive seems ok, so started checking on brake pick circuit and associated components. I could duplicate the problem by letting the brake pick, and during the run push up on the brake switch, the car would do the exact same thing as noted, and log a g21 fault. well we replaced the relays in the brake circuit, and still would get the fault. ended up finding a bad relay1 on the HVIB board.
one contact was severely burned. we are having a hard time finding this DOLD safety relay. may have to replace the entire board. The bad thing is that the other 2 cars are getting the same fault numerous times, and the same contact on the relay is burned.
Just wondering if anyone has had this happen, is it common, and also very concerned that we can duplicate the G21 fault and cause the car to do a normal stop, open the door and not reopen causing door to close on people. Seems the Dold relay was specially made for otis, and is not for sale elsewhere. the car is still down, until we find a relay, or replace the board,

A G21 is a drive fault. It means the drive sent the shutdown command to the mcss. It's a generic code for a drive fault. Sorta like a MLS drive Fault on a gem controller. What type of drive fault are you getting? I believe if you're picking the the brake and the switches you are causing a brake fault(unintended movement) in the drive causing a drive shutdown.(g21). Not familiar with the high voltage interface board or the relay DOLD on it. We haven't had many drive problems with the few in my area.

Is it a GCS controller or was this drive added to an older controller?

While I cannot give out a lot of information on this unit, I will tell you that the drive is now repairable through OSC. They recently announced an exchange policy which reduces the price on a new drive significantly when the faulty unit is returned upon the receipt of the new unit.

Sorry I cannot help more, but with Otis equipment I am limited on what knowledge I can assist with. But as far as the drive goes, I would recommend purchasing a replacement, as I have not been successful in procuring an HVIB board from them; only whole units.

Good luck.

thanks guys, it is a gcs controller. i believe that we cleared the drive fault log, and when we duplicated problem, the drive fault log was still empty. going to have to double check on that, but i believe that is what we had. it has been a few weeks since we removed the hvib board for repair.

well otis does sell the HVIB board. We obtained one, and got car running again. so far so good no faults, but time will tell. the DOLD relays are rly1 and rly2 on the HVIB board.
the relay on the right, rly1 left n/o contact is burned on all controllers. the other controller we cleared last week had 2000 G21 faults. we are going to remove the other relay, rly2 on the hvib board which is i good shape and replace the burned rly1 on the other car. that way we will fix 2 cars with one board, as they are quite expensive. will keep you posted, hope this takes care of it,

Awesome. I love cannibalizing boards. Glad you got it going.

well only lasted 3 days and same thing, at a loss now, everything seems ok, but still this problem persists. uggg dam elevators

Sorry I've never worked on this type. But I do have a question. What does it do if you disconnect DZ?