Looking for a schematic for the rear lights in my truck. I have a 1971 f100 2wd 4 speed. Someone in its previous life decided to install tow lights and cut everything. I assumed connect green to green, yellow to yellow, but somehow I cant get all the lights to work. I can get emergency flashers but no brake lights, running lights but no brake lights with running lights, and so on. I bought the Ford USB shop manual but so far I have found it pretty worthless. Can anyone help me out? Bascially I have three wires going to each tail light. Seems simple enough, but I hate electrical!

 

Here you go:
https://www.fordification.com/tech/schematics_h.htm
https://www.fordification.com/tech/w...m-72_quick.jpg
https://www.fordification.com/tech/wiring/wiring-diagram_70ext-lights01.jpg
https://www.fordification.com/tech/wiring/wiring-diagram_70ext-lights02.jpg

 

Some good references. Thank you. Of coarse in the first link 1971 is not listed! My wiring dont look like the 1970 wiring. It does however look like the 1969 wiring. My bet is it is the model 99, but I guess it could be the model 83. Is there any way to know what model I need? The wiring to the rear lamps are different between the two provided 1969 options (83 & 99).

 

Problem in the turn signal switch will make the brake and turn signals go stupid. My bump had the turn signal cam replaced and the contacts weren't quite right. It had all kinds of weirdness going on before I changed the entire switch.

 

Great! I have running lights, brake lights, brake lights with running lights, and emergency flashers, but no turn signals. Could be the other flasher under the dash. but made good progress this morning.

 

Maybe I am having issues with the contact at the turn signal switch. Everything worked then I ate dinner came back and lost brake and flasher to one side. But wait somehow I have brake if I’m using my turn signal. Both turn signals will work until one decides not to. Then one brake works with the headlights off but they both work when they are on until one decided not to. What a mess.

 

Yup. If I slip a screwdriver onto the turn signal switch and press on either end making better contact lights start working. Man what a pain that has been.

 

2nd the TSS. I had to grind off the pivot point and drill & tap it for a 4-40 button head and washer to keep it tight enough for good contact.

 

Today I was able to pull the steering wheel and have a look at thing. Didn’t help as much as I hoped but if I apply pressure to the switch my lights work. Other than drilling and tapping at the pivot is my only other option replacing the switch? Where’s the best place to get a switch for 1971 f100 2wd bare bones truck? Thanks. Also put all new brakes on the truck today and a new master. Just need new rubber lines to the front and that can be checked off the list hopefully.

 

I would start trying the drill and tap so you can get more even pressure.

 

well I am blowing fuses now, so looks like I will be buying a new switch.