Sounds like you're doing good, let us know the final outcome.

 

This will help you see what the wires are color coded for the flashers.

 

I've made some good progress. Tail lights, stop lights, instrument lights, and turn signals are all working. This is a utility body truck and there are no back up lights. At some point a previous owner replaced the tail lights with LED's that do not have white back up lights. I did rewire for back up lights and I have power on the wires that are capped off for now. I'll look for some surface mount back up lights in the future. Should be an easy fix. The horn is still dead so I'm going to have to pull the steering wheel. There is still the issue of the turn signals working with the ignition in the off position. I don't see any wire leads that could plug into a flasher. I think that the turn signals were rewired at some point into the emergency flasher wiring and that is why they work even if the ignition is off. I am going to continue tracing the wiring and see if I can figure this out. It appears from the wiring diagrams that the turn flasher should be part of the harness on the back of the instrument panel. I did have to solder some wires that were hanging in back of the instrument lights, but the bulb sockets had the wire colors stamped into the metal backing plate and the colors that I soldered seemed to match up to those. Does anyone have a picture of their instrument panel rear harness with the flasher in place?

 

Edit.
The T/S flasher is located on the instrument cluster in the schematic I posted above.

 

Here are some pictures of the cluster wiring that I have. If I read the schematic correctly, it looks like the flasher has wire #44 (blue) and #297 black with green stripe going into the connector. I don't have any plain blue wires going into or out of that plug. I do have a blue with red stripe but that color is used on some of the bulb sockets.

 

I found a few pictures of some instrument cluster harnesses for sale on ebay to use as a reference. Looks like that blue wire is outside of the terminal plug and is a separate female connector that takes power from the flasher to the blue #44 wire and feeds it to the column turn signal switch. I think I have my earlier problem figured out with constant power feeding the turn signals. Looking at the schematic (thanks to all who provided the diagrams) I think I may have been feeding the ts flasher with the emergency flasher power feed, which would explain why there was still power with the ignition off. Everything else is pretty much sorted out except for the horn which is probably the horn switch itself and will require me to remove the steering wheel. I need to get a puller and while I am there I may replace the broken shift collar which is being held together with a hose clamp. I'll post back when I get it sorted out.
Thanks

 

Back in the day the horn relays and the horns themselves were known to freeze up. Usually from years of non use. 1st try grounding the wire at the horn switch and see if the horns blow. Then I'd take a jumper wire from the battery and touch the terminal on your horn(s). if it/they beep that rules them out of the problem. Next check the horn relay. See if it clicks when you have a Buddy push the horn button. If not use a circuit tester to see if power is at the relay. And going through it. Top half of the pic is F100/350.

 

While checking for continuity with a test light at the steering column connector I probed the horn wire and the horn sounded. If I am not mistaken the continuity light was acting as a ground when I probed the wire causing the horn to sound as it normally does when you push the horn button. The wiring forward of the steering column appears to be good. I think it has to be at the switch itself.

 

4 way flasher switch is repaired and put back together. I installed the flasher and something is still not right. There is only one flasher installed and it is supposed to be for the four way flasher only but the turn signals are working off of this flasher. The turn signals do work but the original problem still exists: the turn signals are working with the ignition off. The wiring schematic shows the emergency flasher with a red and red/white wire. The wire that I have has a red/white and also a blue wire under the same connector. The connector looks like it is a factory connection and not something that someone made up by themselves. The other wires look like blue/white stripe and a green with red stripe. I think these may be for the optional cigarette lighter which isn't installed on this truck. Getting closer but still not there 100%.

 

When I get home I will check my 1968 F250 and see if the T/S work without the key. This may be factory correct. Ford changed the T/S switch in the 1969 model year. There was a 67/early 69 switch and a late 69/72 switch. You might have found what the difference is.
When I was a kid I found in my parents brand new 69 LTD, that if I pushed the brake pedal down and turned on the left T/S at the right spot the radio would come on. This without the key on.

 

This help?



(A = Wiring Harness Connection)
Pictured here are the differences in the instrument panels. The '67-'69 panels had a stamped steel rear gauge housing using individually-wired 1895 bulbs. The '70-'72 versions had a printed circuit board and removable 168/194 bulb sockets. The early panel assemblies are not interchangeable with the later assemblies, although all bezels are fully interchangeable

 

I have finally figured out my mess of wiring. A hack job of P.O. adding trailer lights and gauges and some wild wires connected to my pedals for lights I assume!!! My point is never give up because "that mess of wires" will gradually make sense and will look less like a "mess".
Oh it is late, and have not read all of your thread. I will finish reading and may have a little help for you later...........Good Luck........

 

I checked. My 68's T/S do not work without the key.
Looking up the part number for a 1967 F100/350 T/S flasher unit I see there were two choices for some reason.
C7TZ13350B fit a whole bunch of Ford BIG trucks and 1967 F100/350 before serial number A52,001.
C3TZ13350A,replaced by D0AZ13350A, replaced by D0AZ13350C, replaced by C5AZ13350B fit various trucks and vans. Including 1967 after serial number A52,001 and newer F100/350.
Ford called the C7TZ13350B a H.D. T/S flasher. They also mentioned the C5AZ13350B (D0AZ13350C) is for T/S and should not be used with Camper or emergency flasher. It is not H.D.

 

My '68 f250 turn signals don't work without the key either..

 

Looking up the cluster wire harness I think I might have found something. Just posting the listings here for clusters with idiot lights as lights or gauges are not part of the point here.
1967 F100/350 (with "single" transistorized flasher system) before ser #B40,001....C7TZ10B942C. Marked C7TB10B942C, or E.
1967 F100/350 ( with "double" non transistorized flasher system) after serial #B40.001.....C7TZ10B942F. Marked C7TB10B942F.


This sounds like your 1967 is before serial number B40,001 and only used one flasher for both T/S and 4-Ways.
*