Courtesy Light staying on/ Dash lights not working

I cannot imagine what in the ignition switch, is common to either of these symptoms.
All dome lights are controlled by the ground leg of the circuit. This can be a problem as simple as a bad bulb or an incorrect bulb and if all (if more than one) dome / courtesy is on, it could be any of them, although it is more likely that the problem bulb/ socket is not working.

Dash lights. No fun. There is a "bunch" of lamps depending on the car model, here is how it works:

The light switch has TWO power supplies, one for ONLY the headlights

The second feed comes off the tail lamp (fuse if there is one) and feeds the circuits in the switch for park/ tail/ and to the dash dimmer. Through the dimmer control, out of tan wire, to the fuse box and through the INST fuse, and then off to all the dimmer controlled dash lighting on ORANGE wiring. So whatever lamps in the cluster, the radio, the shift quadrant, and the ash tray if used. There might be another 1 or 2. You are simply going to have to chase them all down. You could separate the radio connector, but if that, the short could be closer to the dimmer. You could separate the cluster connector, but again, same deal. Visually examine wiring and harness for a "pinch" AND WIGGLE TEST

There are devices "short finder" You put them in place of the fuse and they cycle like a turn flasher. THIS MAY DAMAGE THE dimmer control, so if you do this, wire the test device to the ORANGE wire side of the fuse clip and wire the power side of the test device to power elsewhere.

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