Help with reverse light wiring for '72 3 on the floor

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Explorer4Hire

Explorer4Hire

10 Year
Joined
Aug 25, 2015
Threads
80
Messages
1,385
Location
Northern Virginia
Hey... really getting frustrated today. Early 72.... I cant get the reverse wiring down. I have a red wire with a blue stripe.... it crosses over to the passenger side, goes forward with harness bundle... and thats it. There is no bullet connection for the switch on top of the trans. Those wires are just cooling out up there. The only connections I have are for white/black wire and green/yellow wire. I think those are for the transfer switch which activates the green light on the dash (also not working yet as I cant locate the transfer indicator switch yet). Anyway, the only other wiring I see are two green/red stripe wires that are up on the driver's side hanging out near the voltage regulator part of the harness... I am stuck on this one...
anyone with a 3 on the floor out there know how yours is wired up? Thanks!
 
The Red with blue (RL) is the correct wire. It shares a circuit with your heater.

Coming out of the fuse panel, the RL wire goes under the dash then out the firewall. The firewall has 2 plugs on the passenger side that connect to the rear chassis harness. The RL goes under the truck, then up to the transmission. (The rear lights, fuel sending unit (YR) and the transfer case switch wires are all running with it).

The reverse light switch is threaded into the back of the shifter housing (might be what you’re seeing?). Its pigtail should have 2 bullet connectors. One that feeds 12V+ from the fuse panel, and when reverse is engaged, it sends 12V+ through to the RL that goes to the reverse light.
 
Last edited:
My harness simply has no connection for the bullet connectors on the trans. I found out last night the transfer switch is not a thing on the direct shift / non vacuum transfer models. That’s why mine has the green light but no lamp was in it. All the connections are there but probably because they just used the same harness for both models. So no light. The reverse light tracing I had done yesterday and I found it exactly as you described with no plug underneath for the switch. I’m going to jump the two firewall driver side green/red stripe wires that are there to see if this was once converted from column shift. Thanks!
 
My ‘67 was converted from column shift to a floor shift at some point in its life. My reverse wiring was wrapped up on the engine bay side of the firewall where the original switch would have been.
 
Well. I can confirm 2 things:

1) I need a new revere light or need to repair the housing.

2) the green and red wires have just changed color and were once blue and red and are intact for the reverse light. Must have been a column shift.

I made a long wire to the reverse light bullet and tested continuity to one of the drivers side firewall wires. Disco.


IMG_6580.webp


Then the other wire gave me voltage on ACC




IMG_6582.webp


So…. I just to make long jumpers to the switch on the housing. No sweat. I also need a new reverse lamp if I can’t fix this one.



IMG_6578.webp


IMG_6552.webp


IMG_6581.webp
 
Mine change colour too, start as yellow at fuse box, a red/blue(purple) splits off to supply power to the switch and then goes back into the chassis and to the light, changing again where the wires re-emerge at the back. Reverse switch on 3 speed boxes is also listed as an option - one may never have been fitted.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom