Car shuts off when i turn on my head lights.

hi, gm vech. are elec.complex with logic that is all there own. im a retired ford tech, and gm would drive me crazy sometimes. now some ideas, your dash light are controlled with an ecm, keep in mind, your dashlights and tail lights are on the same circut. i would check your batt. cables, if your ground cable has a high resistance it could cause issues. in fords they had bad dimmer switches that would cause the same issue. if you have someone with an obd2scanner it might have a code.hope that helps.

sounds Like the Body control module is goin and check your grounds for being Loose and see the could also be in the wiring Harness is a short or the dash panel is shorting out out first by used one then see what happens ther cheap

This is a devious problem which could lie anywhere. So many things not functioning would perhaps be a ground problem. Maybe take some extra care in cleaning the battery terminals, check if the ground wire is connected to the chassis. Do you have rodents in your area? Maybe they nibbled some wire somewhere?

did you check the directional switch. sounds like you have a bad one

Check your fusible links leaving the positive battery cable,wires could be burnt or swollen.just check all wires coming from positive side of battery.Also check all fuses in fuse box.

Could be any of several things. If the crank sensor is marginal and not sending pulses, the fuel pump is shut off. This is for safety. The pump is energized for a few seconds as key is turned in preparation for starting then engine must rotate normally to keep the pump on. If it stops, in a few seconds the fuel is cut off.

Common problem, there is a headlight relay in the power distribution center under the hood that needs changed out.

these are bad about two things the connector on the back of the control head and the ignition switch...

Gm's body control module will recognise your request for head lights automatically, if you've already checked drl, next thing to do would be to leave the head light switch on after shutting off the ignition for 10 seconds then shut them off and remove the key, then start it back up to see, you can also do the opposite start the truck, turn on the lights, turn off the lights, turn off the truck and pull the key, start it back up and see,, This procedure may have more to do with the delay security head light feature, but it all ties in together