Ford switches to GM harness

September 04, 2019, 02:26:08 PM

I'm trying to wire up my factory Ford 1988 Thunderbird multi-function (turn signal), dimmer, and headlight switches using a hod rod (GM) style harness. Wondering if anyone's done this on here and could offer me some help with it. I've been reading the EVTM and I think I've figured some of it out but am feeling pretty unsure about it. I'll keep working at it, but any help would be greatly appreciated. Thanks!

[ FORD MFS ]

[ C238 ]
3 LG/W - LEFT FRONT TURN LAMP > Lt Blue
9 LG/O - LEFT REAR TURN/STOP LAMPS > Yellow
507   - [DIMMER HARNESS] High beams > Lt Green
527R - [DIMMER HARNESS] Flash to pass > N/A
13 R/BK - [DIMMER HARNESS] Low beams > Tan
15 R/Y - [DIMMER HARNESS] Power > Lt Blue

[ C237 ]
5 O/LB - RIGHT REAR TURN/STOP LAMPS > Dk Green
2 W/LB - RIGHT FRONT TURN LAMP > Dk Blue
44 LB - FROM TURN SIGNAL FLASHER > Purple ???
385 W/R   - hazard flasher + out > brown ???
511 LG - stop light switch + out > white ???

[ FORD MAIN LIGHT SWITCH W/O AUTO LAMPS ]

38 BKO - Hot > Red
15 RY - Headlamps > Lt Blue
195 T/W   - Hot > Orange
14 BR - Park & Taillamps > Brown
19 LB/R - > Dash lights > Dk Green

[ GM HARNESS TURN SIGNAL WIRING ]

Lt Blue - Left front turn signal
Dk Blue - Right front turn signal
Brown - Hazard flasher
Purple - Turn signal flasher
Yellow - Left rear turn signal
Dk Green - Right rear turn signal
White - From stop light switch

[ GM HARNESS DIMMER WIRING ]

Lt Green   - High beam
Tan   - Low beam
Lt Blue - Power from headlight switch

[ GM HARNESS HEADLIGHT SWITCH WIRING ]

Red   - Battery feed
Orange - Power from tail light and park light fuse
Lt Blue - Dimmer switch
Brown - Tail & Park lights
Dk Green - To dash light fuse

Diagram of the GM wiring ...

Turn signals

turn-signal-wiring-diagram-third-level-stop-hazard-gm-schematic-data-everlasting-t.jpg

Re: Ford multi-function switch to GM harness

Reply #1 – September 05, 2019, 09:42:29 PM

C238
507 Y 527 R 13 R/BK and 15 R/Y are the headlight dimmer switch and flash to pass switch. EVTM page 159

C113
6 Y/LG from horn relay.
57 BK to ground
151 LB/BK to speed control amplifier.
6 Y/LG supplies the voltage (through the horn relay coil) to the speed control buttons.

Re: Ford multi-function switch to GM harness

Reply #2 – September 05, 2019, 10:04:12 PM

pics