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I have a '68 F-100 with some turn signal voodoo that I cannot figure.
Brake Lights work, Parking lights work, Emergency flashers work (in the dash also), New turn signal switch, New lighting switch, New flasher can, wiring looks good in the back, no corroded grounds (that I can see) - but the turn signals do not work. I hit the bar, up or down, nothing.
However, when the turn signal is flipped and the brake is applied- that particular brake light goes out (the brake light is interrupted by the TSS). Both sides have the same behavior.
I feel like some wiring oddity is going on, or I have one little loose bit somewhere.
From my symptoms, I'm wondering if anyone can pinpoint where I can start looking.
Quick note, there is an amalgam of original (super crusty) wiring, mixed with shoestring repairs and blade-fuse-hacked wires all throughout my underdash (how embarrassing!)
Thanks!
T/S flasher plugs into the back of the instrument cluster. 4 way emergency flasher nestles into a bracket that is retained to the backside of the dash w/a screw.
The 4 way flasher is a heavy duty unit, has a loud CLICK. Was used instead of the "weak sister" T/S flasher with trailer tow, dealers installed it in place of the T/S flasher for people that were deaf.
I figured this might involve chasing down a ground issue. I was just thinking it would be upstream since the other things worked. I checked the bulbs a few months ago, but I'll work my way from the back to front.
Thanks!
Verify that 12v is coming in on the one wire to the turn signal flasher with the key ON.
Then swap the turn signal flasher for the 4-way flasher (assuming yours have the same connector orientation) and see if anything changes.
If you have 12v, and the flasher is good (new parts are often bad right out of the box, which is why I still recommend testing even after a new part is installed), then either the wire to the turn signal switch, OR the turn signal switch itself is bad.
Your switch sounds good since it does everything else it's supposed to. But they do fail, and are probably the most common failure point for the turn signal circuits, aside from PO modifications to wiring.
Sorry if I left anything out. I'm not a total expert on any of this stuff, but I've fiddled with them often enough to have some input. Hopefully it's legit input!
I'd lean towards flasher relay issue. Lack of power to it? Ground? If the turn signal is turning that side off, then it's waiting for the flasher to flash it. Once activated, the relay puts 12v down the line to flash the front and rear bulbs. If they are dark, then the relay is not activating.
Since the brake lights work, I do not see it as an issue with the light sockets or wiring. The brake light element is what gets flashed.
Just a quick update. I put in a new relay to start. no difference. I did notice the connector is seeing some 50 years of deterioration. I might try to wire it directly, but less tugging and prying the better. most of the rubber and plastic is on the crumbly side of the spectrum.
Another note - the brown wire from the ignition switch gets warm when ON. I'm thinking there's a loose wire, cracked connector, or bad ground somewhere.
I'm including a couple of pics to illustrate the area.
Another note - the brown wire from the ignition switch gets warm when ON.
I'm thinking there's a loose wire, cracked connector, or bad ground somewhere, or worse....
1968/69 FoMoCo Passenger Cars, F100/750 & Econoline. 1970 F100/750 & Econoline before serial number G90,001:
The original ignition switch (C8AZ-11572-A) shorted out and caught fire!
In 1970, FoMoCo replaced it with a new switch kit (D1AZ-11572-C / Motorcraft SW-1054) that included a pigtailed wire harness/plug that was spliced into the wiring harness.
There were no recalls back then, it was up to the dealers to notify customers if there was a problem. Some did, but some did not.
If the wires are not spliced, the original POS switch is still in place.
That large "brown" wire is looking like your Pink (more like Salmon color) resistor wire to the ignition coil.
It's supposed to get hot to do it's job, so heat is ok to a point. At least that's what that wire looks like to me.
On some vehicles they actually kept that wire outside of the harness tape and encased in it's own heat-resistant outer jacket so that it's heat did not compromise other wires. Yours looks to be particularly heavy, so maybe the thicker jacket served to keep it cooler on the outside and it would not heat up to the point of melting adjacent wires.
I don't have a diagram for your year truck, but that's what I would say it is.
T/S flasher plugs into the back of the instrument cluster. 4 way emergency flasher nestles into a bracket that is retained to the backside of the dash w/a screw.
The 4 way flasher is a heavy duty unit, has a loud CLICK. Was used instead of the "weak sister" T/S flasher with trailer tow, dealers installed it in place of the T/S flasher for people that were deaf.
I can't find the emergency flasher held with a screw in my 67 F100 dash. Do you know exactly where I should be looking??
I removed the instrument cluster and still can't find the hazard lights or turn signal flasher.
13350 flasher is not located anywhere here. Drawings that NumberDummy posted show it at upper right here. None of the wires or harnesses have any flasher device attached. No flashers found to left of column either.
Hey WOG67, welcome! Sorry to hear you're having trouble. But hey, that's why most of us hang out here now and then anyway!
In your second pic, did that little 90° push-on connector with the Red w/white and Blue (with white?) wires that look to be spliced into the same connector, have anything connected to it?
I don't have the '67 diagram handy at the moment, but Red w/white is one of the Hazard Flasher colors on later Fords at least.
Was that connected to anything when you took the dash out?
11-14-2018, 10:39 AM
