FOMOCO turn signal indicator wiring 1948?

[Timbo405]

have this turn signal setup "Fomoco SXTS-6"? was plum full of 10 ga house wire and big perdy orange wire nuts ( same folks wired my dash back in the day - I suspect it was Ronnie Milsap and Stevie Wonder) anyway - would love it if someone had a diagram for this they'd possibly share? asked over at the HAMB too...
Gracias

 

[Bruce Lancaster]

Lousy picture, but I can't even post pictures at all!
Here's what I think. Don't have time to dig back in the literature...
This is a post-1948 switch for shoebox era Fords that was also sold by Ford as an accessory setup for '46-8 type Fords. Switch came in two flavors, one with about 4 or 5 wires for trucks that had separate turn signal lights and 7 wire for passenger cars using stock parking and taillights as the signals.
'46-8 Fords need to get parking light sockets for two filament bulbs (same bulb as your tail/brake lamps). Ford used a socket from 1950 Ford.
Brake light wire gets re-routed from rear of car to this switch because same filament is brake and signal, so switch turns off the brake connection to whichever lamp is flashing.
4 wires to the 4 lamps, and the tail ones have to be correctly chosen because of brake feature.
I never found a kit, and used a switch from about a '50 Ford in junkyard. I had a hell of a time at this until I finally discovered the brake light feature...once I learned that, I spent about half an hour with the switch and a simple circuit tester and identified the use of all the wires.

 

[Bruce Lancaster]

A process with circuit tester, the little flashlight kind:
As I recall, wires to lights are at the ends of the switch, other wires near middle.
With switch in straight position, find 2 wires at ends that have continuity with a wire near center. You have identified the REAR pair of wires and the terminal that feeds them juice from the switch on master cylinder when brakes are applied. Move lever each way...it will turn off the brake light juice to the side the turn signal is turned to, so you now have R & L rears identified.
The other two terminals near ends are the fronts, either can be wired to either side.
Another central terminal is the input from the flasher. That's at least most of it...damn near broke my head figuring it out in 1968.

 

[rotorwrench]

This was an older thread from the HAMB that has some good add on diagrams. As Bruce mentioned, the signal has to share with the right and left brake lights on the back so those add on switches usually have a wire to the brake light switch and then the circuits are plumbed into the two rear brake light wires as appropriate. Most everything else has to be added with the kit.

http://www.jalopyjournal.com/forum/threads/need-help-wiring-an-add-on-turn-signal-switch.927811/

 

[JSeery]

The one diagram looks like one from the shop manual. Might see if the wiring color coding matches the later wiring diagrams. Ford tended to be fairly consistent on their color coding.

Green - Brake Light Switch
Green/Orange TR - Rear Turn Filament (R)
Orange/Blue TR - Rear Turn Filament (L)
Blue - Flasher Canister
Green/White TR - Front Turn Light (L) & Dash Indicator
White/Blue TR - Front Turn Light (R) & Dash Indicator

This if from the 53 wiring diagram.

 

[Drbrown]

A seven wire diagram from an after market unit.

 

[37 Coupe]

I am a big fan of the FoMoCo SXTS-6 turn signal switch.The first one I had was on my '46 Ford coupe and dealer installed in the early fifties.The units were made by Essex for Ford and in my hometown. The easiest way to fix what you have is buy a NOS switch and wiring and a couple are on Ebay right now.Search 1949 -1950 Ford turn signal switch.They are not easy to find and I have not seen any on Ebay until now. The unit just simply screws into the housing you have.