Last week my headlights started going out driving down the road if I jiggled the headlight dimmer switch they would come back on. So I figured the headlight switch was bad and ordered an acdelco switch form rock auto and put it in this afternoon. Thought everything was great but I don't have any running lights.....
clearence or rear running lights

Ive got headlights, turnsignals and brake lights but not running lights ***?

Ive got the dash torn out the truck and all is all is good with the connections along with the park lamp fuse.... any Ideas??

 

ps part of the trucks wire harness looked a lil burnt at one prong does any body know what wire does what and how would I go about fixing it

 

Can't help with the fix but I was going to tell you on my 1st gen the plug on the harness end got pretty weak due to the heat produced when the switch would cook. You might score a good one at a junk yard. I believe there is an upgrade available to you. It adds a relay into the headlight circuit to eliminate the overheating switch.

 

thats what Im afraid of....having to work on the trucks wiring harness just great.....

 

If you would have gone to the dealer they could have sold you the switch with a pigtail to repair the wiring

 

there is usually enough wiring in the loom to cut back beyond any fried sections, replace with all new spade connectors, takes longer then a plug in with the dealer pigtail, but that way you know your making all new connections to each wire.

 

theres probally 10 wires in the harness that goes to the switch with no room to cut and splice it would be a royal pain in the butt probally have to pull the dash but I think the switch is bad. I unhooked it this morning and pluged it back in one of the prongs was bent and got it strait and got the running lights to come on but they wont stay on so I guess I need a new switch. Having to get a new switch is a whole lot better than replacing the wire harness.

 

On my 03, you can push the harness back through the dash and bring it out under at the pedals to give you more room if needed.

 

Got new switch and its still doing same thing....

pull out to normal position for park/running lights = nothing

pull out almost till the headlight position = parklights

pull all the way out for headlights = headlights on parklight off

***.......

 

Are you positive the fuse is good? Bottom row, 10 amp on mine. Partially pulling the switch and the parking lights illuminating is normal. There is a tiny amount of contact from the hot headlight wire to the parking light circuit if you position the internals just right. The same thing happened to me while troubleshooting mine and just like you I bought a switch when the old one was good. My problem only involved the lights on the bed, the front parking lights and cab lights worked so I can't offer any help to your problem. You need a FSM to chase wires.

In the first post you said you jiggled the dimmer switch. Did you mean the multi-function switch on the steering column? If so, that may be the problem, not the headlight switch.

 

yeah fuse is good, when I was talking about jiggling the switch I was talking about the headlight swich on the dash not the high/low on steering colum.

 

Sounds like a bad switch to me. I would have said wrong switch, except for the bit about stuff coming on just before a detented position, then nothing when in the detented position, if I am understanding correctly.

I would disconnect it from the harness and check it with a multimeter. Do you know how to use one, or have a buddy who does? It would not be all that unusual for a manufacturer to have a run of bad switches, especially with world wide sourcing.

 

As I said, if you have a pull switch like mine, and I'm pretty sure you do, it is normal to illum the parking lights between detents. I found that out with a multimeter and the diagrams in my FSM. If you are still loking it is a PK/RD wire from the fuse (15A, I said 10A in error) to the switch that provides power to the parking lights in both park and headlight detent. That wire would be hot all the time if the fuse is good. If it is not, either the fuse is bad or the wire is broken. If you have power to the switch then check the wire from it to the lights BK/YL. Every bulb in the circuit is powered by the same color, but since none of them are working the break would be probably be between the switch and joint connector A which is black and mounted near the fuse block. Since the lights do illum with power from the headlight circuit, I'd conclude that the BK/YL circuit is good. That leads back to bad fuse or broken PK/RD wire. These colors are from the 97 FSM, yours may be different.

 

just go to Napa and get the new switch with harness. It comes with a warranty. It'll work that way. Been there done that.

FYI, there was a recall for this problem, roughly from 94 thru some 97s were affected it think. Check it our or maybe some one else has more info.

 

Update... I got a switch and the pigtail harness from a friends wrecked 1/2 ton last week. I guess his had gone bad b/c it had heat shrink with some kind of glue looking stuff coming out of it. Anyways I spliced it all into mine and I got headlights working properly now. However I got a wire jiggled loose for the lights to my guages and the pyrometer is acting up now its always someting, I had them wired into the fuse block but I think Im going to route them to the block up under the hood just the redo them.

I got bigger things to worry about now I hit a fence post (didn't know an old fence was there) at a field party running about 20mph, ripped off my tow mirror, hit right at the tire and scrapped down the bed and took off my taillight. Its fixable w/a little bondo but the worst part was I got it painted 5 months ago with 08 ford high per white, w a met gray 2 tone. Didn't mess up any of the gray though. Just needed to vent a little