We had a problem this last week with our '03 Dodge Grand Caravan — the dash lights went out. Completely. Instrument panel, radio, heater controls — all unlit. My first thought, naturally, was a fuse.
However, when I looked at the fuse box, I couldn't find any fuse that looked like it controlled the instrument panel backlighting. Web searching turned up a few things, including a fixya entry and a DodgeTalk.com forum post which document the same problem and an odd fix: disconnect the battery or otherwise cut power to the computer.
So, I went out and pulled the IOD fuse (Ignition Off Draw, controls the power drawn when the vehicle is off) for a couple hours. Disconnecting the negative cable on the battery would accomplish the same thing for this purpose. After putting the fuse back in, the dash lights worked.
Piecing things together, particularly with the insights from the DodgeTalk post, it seems that the issue is a computer problem — sometimes, for some reason, the computer will stop turning on the dash lights. Disconnecting power to it for a while resets the computer, allowing the dash lights to start working again. Weirdest van repair ever, but it works, and here it is documented so others can hopefully find that the solution does, indeed, work.
And no, the computer did not start singing ‘Daisy, Daisy’ as I disconnected it.