You may be surprised to hear that the dome lights on '57 Chrysler coupes are not switched by the door switches. I first noticed this on a 57 Saratoga coupe that I was restoring -- when a door was opened, the map light above the instrument cluster and the map light over the glove box worked, but not a glimmer from the dome lights. A check of the 57 service manual wiring diagram showed nothing, but a check of the 58 service manual showed that the dome lights (on coupes) are not switched at the doors. I think this was a step backwards by the Chrysler design staff -- the 56 dome lights are activated by the doors so why regress for 57? We'll probably never know.

For what it's worth, the 57 dome lights are activated by the switch on the driver's side dome light bezel. The same is true for 58.

So what is all the fuss about dome lights? If you check the wiring diagrams, you'll see that the 57 dome light circuit is always at +12 volts AND it has no fuse. The same is true for 58. I was shocked (no pun) to find that there are very few fuses in the entire car. The clock and radio carry in-line fuses, the headlight switch and the wiper switch carry circuit breakers, and if you have power windows and/or seat, there are breakers for those, but the rest of the components have no fuses. In the case of the dome lights, the power wire runs from the ignition switch through the driver's side rocker to the trunk and up through the C pillar, under the headliner and insulation forward to the dome light. There are all sorts of sharp metal pieces along this route. As the wire gets old and the insulation gets brittle, plus the years of shaking and bouncing and normal vibration, the insulation can be cut exposing unfused 12 volts to ground. The last place I'd want to have a short and a fire would be in the headliner with the fabric and old insulation ready to burn, not to mention that it would be so close overhead. But there is an easy fix.

There is a standard connector in the wiring harness in the trunk. With the trunk cardboard pulled away, this is the original wiring. The connector is the white piece in the picture center.

A standard in-line fuse can be installed at this location to protect the dome light circuit.

 Not only is it out-of-sight behind the trunk cardboard, it requires no cutting of the original wires. Although it would have been better to install the fuse further "ahead" in the circuit, I didn't see a convenient place and settled on the trunk location.

Here is the fuse installed before wrapping the exposed connections with electrical tape.

This information is provided without warranty or guarantee. Use at your own risk.