I just installed a new Sony head unit for my 05. And attached the dimmer wire which I have read that others have had the same problem of when I attached it, my instrument panel for my speed, RPM, gas and so forth, lights went out. I took the dash apart to look at the dimmer switch after checking all the fuses both in and outside the cab. And when I pulled the dimmer switch the dash light up (with or without the headlights being turned on) but my temp display shut off when the head lights are turned on. On top of that my check engine light won’t go off and my traction control warning lights are on, even after I reset the computer by disconnecting the battery for a time. So i am running out of things I can think of, and any help would be great!