I replaced the motor on a Tac 20 and now the doors open and close significantly slower.

The door operator board is a 6300PA 2 or 4 and has MDC, MDO & RST buttons. Can I do a learn run on this board w/out a service tool?

You will need IMS or a UIT tool to learn those doors. Same goes for Dover, I remember swapping a motor on a DMC and running into the same issue. Good luck

To do a learn run:
1) Car top inspection
2) Doors full close or full open
3) Hold reset button for about 45 seconds


The door operator board is bad. It holds the learn run for a few door cycles and then defaults to the slow speed.

Thanks

Sounds like a bad encoder. I am not farmiliar with that door scan procedure. If you don't have IMS, you should order a UIT to do a proper door scan and be able to verify it took and changed the travel value. 6300HL1, I also have a part # for a 6" piece of ribbon cable so you can access the UIT while plugged in.