[Dad & Mom] Chair remote

Dad's "new" chair lost one direction (down, I think) Carol worked around it by hooking up the remote from another chair. Some of the buttons were funny, but it works.  I couldn't see anything obviously wrong with the remote, but found a replacement at a reasonable price, so I got it. But the new one acts the same as the old one, so it looks like the problem is not the remote itself, but the control box in the chair.  So the borrowed remote is back in place, and I've taken the control box to repair or replace.  Blaine