Can't dim headlights on c3 corvette

bad connection or bad earth check all connection or bulb

Daytime headlight issue ? No , no sensor behind the front bumper . No Daytime time head lamp issue , doesn't turn on the instrument panel light's . This is more then likely a remote dimmer module problem .
Interior Lights Dimming Circuit Description (Pontiac)
When the park lights are on, battery positive voltage (B+) is applied via CKT 32 (YEL) to the remote dimmer module. The interior dimming switch in the lamp dimmer switch is a variable resistor which applies the dimming input via CKT 44 (DK GRN) to the remote dimmer module. The potentiometer in the lamp dimmer switch cannot provide enough current in order to operate the incandescent lights. The remote dimmer module amplifies the current, applying a variable voltage to the incandescent lights. As the amount of current increases, the lamps become brighter. As the amount of current decreases, the lamps become dimmer.
The radio, heater and A/C control assembly, instrument cluster, and passenger climate control each has a vacuum fluorescent (VF) display. When each module receives an input that the ignition switch is turned to the RUN position, each module activates the VF display at the full intensity. When the park lights are on, the radio receives the dimming level from an input on CKT 8 (GRY). The radio then relays this information to any other modules with VF displays. All modules with VF displays then adjust the dimming level of their VF display in order to match the level of the incandescent lamps.

That is a common problem, the switch needs changing if the high and low beams do work, the only problem is that it's an expensive part to replace, try a local wrecking yard they should have a bunch of suitable replacements at a reduced price.

sounds like a bad dimmer switch.

This is very common. the headlight switch is bad. replace the switch and that should solve the problem.

i have run into some that the dash lights dont work at all or they come on and off while driving.
the switch goes bad. there is also a dimmer switch . the dimmer switch controls the dim or brightness off the lights.

i don't have a real good answer, soooo just remove the dome light bulb so you can drive it

If I'm understanding you correctly sounds like dimmer switch is defetive or there is an open in the circuit. remove dimmer switch from circuit and use a set of jumper wires and jump the circuit connector and see what happens .If light come on when switch is bypassed the switch was the culprit . If not then your into surgery. Gonna need repair manual and do exactly what it says to hunt for the open, lose wire etc.

You need to take the vehicle back to whoever repaired it for there's a rod running down from your dimmer switch to the actual dimmer switch mounted above your ankles which should be white and/or green and it has two 5/16" nuts or 8 mm, same thing, and the headlight dimmer switch is slotted to move it up or down the column to make contact. You can do this yourself in loosening the bolts, turning on the headlights, and when they stay on, lock down one of the 8 mm bolts, then check the dimming feature and if it's still not correct, loosen the bolts just enough to move the switch (with the rod coming down from the steering wheel) just enough to "fine-tune" your adjustment.

"00 Buck"

there could be a bad connection between your dimmer switch and the lights themselves. often times through vibration and wear and tear the connectors degrade. check this first. also the dimmer switch itself could be the cause.check all the connections associated with the panel lights, look for loose wires and/or bad connections if there are none replace the dimmer switch

headlights rlun on high beams at all times dimmer switch is designed to interupt the circuit so id say your problem would have to be at the dimmer switch check the plug and linkage