lighting problem

[Nolan8954]

I'm having some sort of electrical issue with my 1958 Thunderbird. The headlights are dim when on. Not sure if it's related but mentioning the clock has never worked.

[gasman826]

quick and dirty:  run a jumper wire from the negative (-) side of the battery to the ground terminal of one of the headlights.  If headlight brightens, there is a grounding issue.  If not grounding issue, run a jumper wire from the positive (+) side of the battery to one of the positive terminals on a headlight.  If the light brightens, there is a supply issue.  Supply issues usually mean corrosion/connection issues and will cause heat.  Touch the headlight circuit paying attention to connections, headlight switch and dimmer switch checking for heat.

[Ford Blue blood]

As Gary says, do the quick and dirty to start.  More info would be helpful the diagnose the issue from afar.  Headlight switch has a built in circuit breaker.  The switch is fed directly from the "Bat" terminal on the ignition switch.  Are all the lights dim (park, tail and dash) or just the headlights?  Both hi and low dim?  Do any lights dim when you push the brake pedal?  Does the car spin over and start as it should or is it slow?  Do the headlight brighten as RPM is increased?

Clock has nothing to do with this issue as the common problem with them is a dirty contact on the whinder switch.

[Malcolm8112]

These might be of use
https://ford-manuals.com/product-category/ford/thunderbird/1958-thunderbird/