Toyota Repair: lost dashboard illumination, toyota tercel, fuse panel

Question
My dad gave me his 1991 ,4 door toyota tercel. He said the dash lights started flickering and just died one day.I started looking for the problem the other day. I figured id start at the dimmer. I unhooked the switch and ran power from the fuse panel to the positive , green terminal{i have a wiring diagram for a 1992. it doesnt tell me where the components are located however}I got the dash ,console to light up. Heres my promlem, it only lights when the headlight and parking light switch are in the off position.. When i turn on the headlights , the dash lights go off, even while the dimmer has the power to it. I checked the dimmer swich it works, as do the headlights and parking lights.I just dont know if there is a seperate relay for illumination, the same relay as the parking lights, or no relay, i dont know where to look next. All the fuses are good

Answer
There is no seperate relay for the dash illumination, the rheostat control get 12v directly from the headlight switch the other side goes to ground, if it was shorted to ground the dash lights would be on full bright all the time, if it was open there would be no dash lights because there is no ground and no current flow, I assume that you made a jumper from 12v to the green and yellow wire and left the rheostat connected.
Remove the jumper and see if there are 12v at the g+y wire, if not, the problem is the light switch, it may available seperately or you may have to replace the entire combination switch.