Need some help with headlight wiring (1 Viewer)

[DFXR]

'85 FJ60.

First off, I have the IPF headlight loom in hand and ready to install (thanks Kurt). But I don't think it's going to do me any good until I solve this problem with my stock right headlight connection, because from what I can tell the IPF loom plugs into that connector for switched power.

The problem - a few weeks back I was just going to upgrade from sealed beams to 55/60 H4s with Cibie knockoff lenses, while keeping the stock harness. When I unplugged the right headlight connector, the brittle plastic housing disintegrated in my hands. It was not OEM - it was a cheap generic connector that a PO or PPO had spliced in. Since then I have not been able to get that bulb to light properly. It is dim while the left bulb is fine. (Until the moment that I went to unplug it, the headlight had been working fine.)

I have tried multiple different replacement connectors, from another generic Dorman unit to a nice ceramic H4 connector. Always butt splicing and heat shrinking with good connections. Nothing seems to work. I found that the RH fuse (10amp) was fried early on, and I replaced it and it has not fried again. But still the bulb is dim. I have checked for bad grounds and loose connections and come up empty. I have swapped out the bulbs, and swapped sealed beams back in, all with the same result - OK on the left and dim on the right.

What I want to know are a few things - can someone confirm the correct wiring orientation for the 3-blade RH connector? I have two red and blue wires and one red and green, that I assume to be the ground.

Also, could this be related to a sick alternator? I wouldn't expect much of a change because the new bulbs are still pretty low draw.

Last, can I flip the IPF loom and use the LH stock connector to tie it in, instead of the right?

Thanks for reading this far...

DF

 

[Output Shaft]

Headlight wiring harneses usually get their "trigger" voltage from one of the headlamp plugs. It doesn't matter which one. The unused one is typically just wrapped up well to insulate it and left to dangle somewhere.

If your new harness works this way, but has its connector length fitted for the RH bulb, you can definitely lengthen that pigtail by cutting the cable and splicing in an extension to reach the LH headlamp wiring plug.

I wouldn't worry about the low current carrying capacity of your RH headlamp wires. Once you rig your new harness to the good LH plug, you'll never be using the RH power source ever again.

The headlight grounds on the FJ60 run together in a common grounding junction connector tucked behind the instrument panel. My suspicion is that it has fried. That's a good place to start anyway.

Is my alternator about to eat dust?

The alternator dying would not damage just one side of the headlight harness.

Wire colors for the headlamps are noted in the FSM.

 

[DFXR]

Thanks. I think the best bet will be to bypass the RH connector as you suggested. I was just hoping not to modify what looks like a perfectly great new loom... more opportunities for issues once I get my hands into it.

I found the wiring diagrams in the body-chassis manual, but couldn't make sense of the color specs. It shows a Red-Green (R-G) and a Red-Yellow (R-Y) going to the RH and LH headlights. I have R-G but definitely no R-Y. I could be reading it wrong.

 

[Output Shaft]

Doesn't the new wiring harness have a male plug that plugs into the female plug ... that normally plugged into the bulb?

If so, just plug it in. You don't really need to know the wire colors.

 

[DFXR]

Yes, and I could just plug it in... but if the existing RH female connector has some kind of short/corrosion/bad ground between it and the switch, then I'd hate to rely on it for the trigger. I'd rather fix it, or take it out of the equation by bypassing it.

Rather than cutting and splicing into the new loom to extend the male connector, I think I can just make an extender that plugs into the loom on the right side and runs over to make a connection on the left side, which is working fine. I will check with Kurt at Cruiser Outfitters to see if this makes sense.

 

[DFXR]

OK, here's what I did, in case someone else has this same random and specific issue.

The IPF headlight loom is made to fit on the right (battery) side of the FJ60 and get its "trigger" through a connection to the existing RH headlight connector. My RH connector was not working properly so I couldn't/didn't want to use it. Confirmed with Kurt at CO that the trigger can come from either side.

I did not want to modify or splice into the new loom, and I did not want to move the loom to the to the left side of the engine bay. So I made an extender to go across:

female H4 connector > 3 X 5' 14 gauge wire w/ conduit > male H4 connector

Plugged it into the IPF loom on the RH side and ran it across to the factory headlight connector on the LH side. Did everything else according to the IPF instructions.

Everything works now, lights are nice and bright.