76-77 Dome Light Question

[Coolerman]

Real time help needed.

As much I have messed around with these wiring harnesses over the years, there are still many thing I do not know about some of the wiring sub-harnesses since they are not attached to the main harness.

Case in point:
On the 76-77 Dome light that is mounted to the hard top: Where does the wire route that feeds this light? Does it go across the top above the door to the wind shield like the early trucks? The early trucks had a female bullet connector that exited the windshield wiper harness and the dome light had a 21" extension that plugged in there then ran along the top gutter and plugged into the light. How does the 76-77 accomplish this? I have someone wanting this extension harness but have no idea where it goes or is it a single wire or what. A pic of be super helpful...

 

[GA Architect]

Mark,
That is a single wire circuit. It comes out of the fuse box and goes up the left/drivers side windshield to a connector (see photos below). Then it heads back in the roof channel above the door to another connector. Then down into B pillar to the light.

 

[Coolerman]

I love MUD!

So the wire is completely hidden inside the pillar. Is that the female bullet connector in your second pic at the top left of the wind shield? If so I now have enough info to measure and make the harness. I assume the light grounds via the mounting screws to the pillar?

 

[thebigredrocker]

Even though GA Architect answered the question here's links I was gathering for the "saint of FJ40 wiring"

Dome light help

I've searched the forum and need some feedback. I have a 76 FJ40. The dome light has never worked - switch was frozen. I bought a new dome light (1 wire hookup) and plugged it into the bullet connector (red w/ black stripe). Turned the switch and nothing happened. Unplugged the connection...

forum.ih8mud.com

dome light wire path

so i have the wire from the dome light, across the top of the driver door. then i dont have anything heading toward the fuse panel or dash. what is the correct path from the corner where the hard top meets the windshield frame to where it needs to plug in? is the hot female bullet in the...

forum.ih8mud.com

Dome Light

Two questions for you. 1. What size are the screws needed to attach the dome light? 2. How do you run the wire for the dome light? I can see a red wire inside the door jam where the dome light is attached but I can not see where it comes out. I do see the other wire up by the windshield...

forum.ih8mud.com

 

[thebigredrocker]

Coolerman- I have yet to install my hardtop, so was able to uncoil my 12/75 interior light sub-harness wire and measure it. The sub-harness wire itself 35". It is Black/red stripe. I have it plugged in to a short Red/Black main harness wire the exits main harness near the headlights branch.

 

[GA Architect]

I love MUD!

So the wire is completely hidden inside the pillar. Is that the female bullet connector in your second pic at the top left of the wind shield? If so I now have enough info to measure and make the harness. I assume the light grounds via the mounting screws to the pillar?

Yes (hidden in the pillar)
Yes (female bullet connector for the hidden line down thru the windshield)

Yes (Light grounds via the mounting screw)

Here is the connector for the light to the extension that is in the roof channel. **Note that the extension has a protective covering that basically runs the length of it. (well, mine does)**

 

[Living in the Past]

I'll add the second wire was added 10/81 when the switch for dome on the A pillars was started. The routing thru the windshield frame ran thru the end of the 40 series as far as I know.

 

[thebigredrocker]

Hmm. So GA, you have two sections of sub-harness.

 

[GA Architect]

Hmm. So GA, you have two sections of sub-harness.

No, ...Not sure of the total sub-harness sections for this circuit? However there is one section/extension/jumper, and I'd say it is about 33" long (+/-), from the windshield to the dome light. I would guess the reason for this is two things: 1) makes changing out the dome light unit easy. 2) leaves the wiring in the windshield pillar while it goes topless.

 

[Coolerman]

Awesome guys!
This is what MUD is all about: Sharing the knowledge to make owning one of these money pits a joy.

 

[GA Architect]

Coolerman- I have yet to install my hardtop, so was able to uncoil my 12/75 interior light sub-harness wire and measure it. The sub-harness wire itself 35". It is Black/red stripe. I have it plugged in to a short Red/Black main harness wire the exits main harness near the headlights branch.

Rocker - You could be right about having two sub-harness wires? I've not traced mine from the top of the windshield down to below the dash, and on to the fuse box....If you have removed yours, then I guess there are two sub-harness/extensions/jumper wires? My apologies.

 

[GA Architect]

Awesome guys!
This is what MUD is all about: Sharing the knowledge to make owning one of these money pits a joy.

Mark,
I believe Red is correct, there are actually two sub-harness/extensions in the '77 dome light circuit. Per the total harness' I've seen ('76 harness below grabbed from MUD), I think either the #48 or #49 connection near the fuse box for this dome light. That would mean there is an extension from that connection, up through the windshield to the connection I show in post #2 & #6. Then another extension from there to the dome light itself, post #6.

 

[Ackcruisers]

Thanks for the helpful post. I just made the dome light sub harness for a 1976 FJ40 soft top. My truck did not have the hole at top of windshield frame since it was a newly fabricated. What is surprising is there is no BW ground wire on sub harness as it grounds to the screw that attaches to the light fixture on B pillar. I like having dedicated ground wires and do not like to rely on any screws that act as grounds to body.

Sections Made:

SECTION A: There is RB wire with female barrel connector from main cowl harness above fuse panel on drivers side. This section A runs from from barrel connector up windshield frame out to a 3/16” hole at the top. I attached a barrel connector as shown.

SECTION B: RB wire with barrel connector with sleeve inside top of door channel and another female connector at the other end.

SECTION C: RB male barrel connector wire through a hole at top of B pillar and down to female barrel connector that attaches to the switch male barrel connector.