Dashboard lights not working after installing aftermarket stereo...Fuses all look good?

Okay..I have a 2006 Scion Tc and my boyfriend installed an aftermarket double din stereo. well everything was fine and dandy and working properly...then we had 2 orange wires left over, one on the stereo harness, and the other on the harness adapter that I bought for my model car. Well even though everything was working fine without connecting them together, the diagram said they were illumination wires so we connected them. After that my dashboard lights quit working (the speedometer, gas, and RPMs lights) only those. MY headlights still turn on. We checked every single fuse and none are blown, we checked the wiring and everything is fine, we even unwired the two orange cables and still nothing. Then we took the new stereo and adapter harness out and hooked up the factory stereo back in and they still don't work. So what we did for the mean time is that we wired the orange illumination wire to the yellow on the adapter harness and this is the only way they turn on, except for they stay on at all times until I take out the key of the ignition....any ideas on what it could be? please help!

Did you ever figure out this issue, I have the same car with the same issue...

sounds like you disconnected a wire that goes to the switch that controls the dashboard lights.

You have wired the dash lights to the always on power lead. You need to find the lead that comes on when you switch your lights on​ and wire it to this.

were you able to fix it? post is a little old.