No RUnning Lights

Hey guys its been a while since ive been here(busy rebuilding a chevy motor with my free time) but i got a problem thats stumped me. My taillights will not turn on when I am using my nighttime running lights. The headlights work fine. THe brakelights work fine but as soon as i take my foot off the brake there is no running lights. I replaced the headlight switch thinking it was defective and now the dashlight will not turn completely off its like a very dim light even with the key out and the truck lights off? THere is a bunch of loose wires under the tailgate by my trailer hitch along with a ground wire that has nothing to connect to?

Any help would be appreciated

BIGGREEN

Hey Big G,

Sounds like the dash lights are getting back-fed from something.

First thing to do is sourt out all the wire hanging under your tailgate. Often wires to a trailer hook up get chafed and cause problems.

The ground wire obviously should be attached to a clean spot on the frame or body.

The rear circuit for the parking lights are powered through a brown wire for both sides. That wire is energized when the headlight switch is turned on.

Check for power at those brown wires. Also It is important to be sure the light sockets are getting a good ground. Without a ground the parking lights will not work.

Also check that the correct bulbs are in stalled. The rear stop/park/ turn sockets require a double filament #3157 bulb, not a single filament #3156 bulb.

Good Luck, and let us know how you make out.

Thanks for the help man, The ground wire is grounded to the trailer hitch but connects to nothing(it is cut but there is no other wire under there to connect it to)? Also when i use the turn signal say for turning left I can see a faint blinking in the right taillight as well?

"....a faint blinking in the right taillight as well"

This usually indicates a poor "ground"

Ditto Bully.

You have to physically check that the black wires at ALL the rear bulb sockets are actually running to a good ground.

This sounds like someone carved wires up. You have to look at each circuit and check the grounds....or you can dance with someone else's ***** up forever.

I believe that all the grounds run back to the front under the dash. A good suspect for bad grounding is the connector just under the driver side rear bumper on the frame cross member. They have a reputation for corroding, even to the point that the wire breaks off the connector. If you have a trailer hitch, it is inserted in the circuit at that connector. The trailer hitch connecter is T shaped. Remove it and put the two remaining ends together. Tug on all the wire going to the connector to see if any of the wires are weak, check the condition of the contacts for corrosion.

Good luck,