RS2K

I have an '88 Subaru XT6 with a 4EAT transmission that works seems to only work in 2nd, 3rd, and reverse. The hold button does not light up and when I put the selector on 2nd the light on the dash for 2nd does not light up. I tested the HOLD switch and it is good. I also unplugged the TCU that is behind the driver's side trim piece and there was absolutely no difference in shifting. The POWER light does not ever come up on the dash either. I am guessing that the TCU is bad but I am not sure. One day the transmission just started acting up like this without any other hint of trouble. Thanks!