I was testing the wiring on my truck to see if I could find out why none of the lights (except my headlights) on my truck dont work.
And I was wondering if a bad light switch could cause all the lights but the headlights to not work?

 

This summer I was having electrical problems in my collumn. I ended up having to rebuild the entire harness because the previous owner didn't notice a way to disconnect all the wires that run up the column and had cut them all and halfa$$ hooked them back up. I swear some people need to have their tools taken away. The moral of the story is some thimes you just are gunna have to take it apart piece by piece until you find the problem.

 

Does anyone have a wiring diagram for the lights then to help me out
Thanks

 

unplug the switch and see if there are any rusted pins on switch,check harness side also

 

I'm trying to decipher a whole bunch of crazy wiring in my truck, too. A circuit tracer (aka circuit tracker, cable tracker) makes the whole process a lot easier. Clip one end to the wire you want to power, one end to ground, and then wave the "magic wand" to follow the circuit all the way to where it dead-ends (usually at a corroded connection or blown inline fuse you didn't know about or whatever). You can do it the other way, too, starting at the fuse block when you know your power source is good. These are pretty useful in wiring other stuff, too- telephone/network cable, home wiring through attics/basements, etc.

Mine was about $20 and mfg by "Cen-Tech," though apparently no relation to the CenTech brand wiring harnesses. Better units obviously cost more; and are probably better able to pinpoint a wire & go over long distances (and these are probably easy to borrow/rent), but mine works well enough to supplement what I can see. As I understand it the forum rules don't let me give you advice on where to buy one.

 

Sorry, wish I could be of some help. It sounds like a job for ALVIN. Yesterday I was having electrical issues and ALVIN threw me some good information/advise and got my mind right to boot. Wiring, plumbing, and exhaust pipe and I don’t mix very well, but good luck!!

 

Well for anyone interested yes a bad light switch can cause all the lights except the headlights to go out.

I took out the switch and my dad put his meter on it and only one contact had power when the switch was on. So we drilled out the rivets and took it all apart and cleaned up all the contacts inside it and put it back together and stuck it back in the truck. Now three of the four front marker lights come on both tail lights come on and the dash light dimmer and dash lights all work now.

Just need to figure out the brake lights and turn signals now.

 

You can buy a new original 1977 factory Ford F Series Truck wiring diagram from helminc.com for $10.00 + shipping.

Helm also has the owners manual.

Helm has printed all of Ford's literature since the 1940's.