license plate wiring guidance? 81 BJ42 (1 Viewer)

[The Beej]

i had thought the license plate bulbs were out on the new to me 81 BJ42 i am fixing up
so when I took the plate holder off to refurbish and paint, I replaced the bulbs,
yeah they were toast but no. new ones didn't fix it
got underneath to look at the wiring and lo and behold the wires that led away and went down through the body went no where, just dangling there above the back right tire basically
with a a multi pin female connector on the end.
my question is where should this connect up to give me power to the plate holder for lights at night
so I don't get pulled over. i'm not a wiring genius or too mechanically inclined, i am well aware of the 24V wiring but don't know where I should run power from to this connection?



cheers

T

 

[73FJ40]

It just so happens that @Coolerman has a wiring diagram for a 1981 BJ42 on his website:

http://www.globalsoftware-inc.com/coolerman/fj40/schematics/BJ42/bj42_wiringdiagram.pdf

The diagram indicates that all of the 'marker' lights, including the two license plate lights, are fed with a solid green wire and then grounded with a White wire with black trace. They're located on the diagram in the lower right corner.

You didn't mention whether or not the other marker lights are functional; theoretically, if they are working, you could splice into any of the other green wires to get power, and any white/black wire to get ground.

This all assumes the previous owner didn't install his own wiring schematic.

 

[The Beej]

thanks for the link. no the marker lights don't work as you say they are wired with the plate lights and nothing at all is powering them.
so basically I am wondering where to pull power from for these lights and the connector left hanging naked in the rear passenger wheel well.
apparently the wiring for these lights was never re done when the aqualu body was installed

 

[73FJ40]

Okay, so it's time to get a test light and determine where the marker light circuit (solid green) is live. It may be at the connector that's left dangling, if not, further up towards the firewall.

If you're not handy with wiring, @Coolerman may be able to build you a wiring harness to fit up to your dangling connector, if that is still live. Use the color codes on the wiring diagram to check to see what's working and what isn't. Also, track down the type of connectors on your lights, whether they are stock or not. Coolerman has many of the parts for the wiring connectors, but I don't know if he has them for your particular truck.

 

[The Beej]

thanks for the help
nothing is live because nothing is connected to the connector that then runs to the plate lights and marker lights
it is like the power wire was just never run to this connector, it's like they wired the back end stuff then forgot to run power to it
so I just got to run power from somewhere, totally not handed with much except a beer,

thanks for your help thought greatly appreciated will try the coolerman


cheers

 

[73FJ40]

Okay, so there is likely another connector up at the firewall, which feeds the harness going down the chassis frame to the rear. Look for unplugged connectors there.

 

[Bronevichok]

here is wiring for my JDM BJ44

 

[The Beej]

here is wiring for my JDM BJ44

View attachment 1451817

thanks for the pic

 

[The Beej]

Okay, so there is likely another connector up at the firewall, which feeds the harness going down the chassis frame to the rear. Look for unplugged connectors there.

okay I''ll take a look on the firewall thanks for the tip

cheers
T

 

[45Kevin]

I'm in the middle of making a new harness for the back of my truck. It's an FJ but the back end has got to be almost identical.
The license plate light, the side marker lights and the tail lights all work off a solid green and white/black wire.
The green comes from the 4 wire plug (I'm not positive because I took my old harness apart without noticing and there is a solid green from the three wire plug as well) at the fire wall. The white/black comes from the fuel sender plug. I don't understand it but it does on the old one.

The green wire goes to all the back light positions, I think (I haven't got that far yet).
The white/black splits into three at the back of the truck, and one each go to the side marker lights, and I don't know where the other goes. Again, I haven't got that far and the old harness kind of disintegrated, melted together when it got to the back cross member where the PS marker light comes off the harness.

I have been scouring this site all night looking for ideas.

Coolerman is very busy right now, so I'm not expecting him to jump in with the answer anytime soon.

 

[45Kevin]

I stared at it a bit longer and I think the third white/black will bolt to the back cross member of the box. There is a sort of non-stock looking wire there now that goes to the frame. That would mean that the tail lights, back-up and stop lights all ground through the housing. I'll pull one off tonight to confirm that.

 

[Solace in Solitude]

As @73FJ40 said, the marker lights and the license plate lights only require two wires... One ground/earth (white-black) and one taillight (green) to provide power.

The license plate lights are a subharness, to the rear harness and are grounded (white-black wire) to a screw on the back door. The green light spots to feed the two license sockets.

I can't recall whether the rear marker lights are a subharness, off the rear harness, or actually part of the rear harness...

Regardless, to make it legal, just tap into the green wire and run current to each marker light and each license light... Then, tap into the white-black and run to each marker and the rear door (license). Your lights will work, when you have the taillights on.

To make it stock, @Coolerman can fix you up with whatever you need.

Good luck!

Edit: Note, the marker lights are generally grounded to the body... But, it's always better to explicitly ground them, with a white-black ground wire.