Mystery AE86 JDM dash loom plug

[parrot]

I have one plug my JDM under dash loom I can't identify, and I have got lots of printed resources at home to suss it out. The loom is out of a levin so no retractor motors or whatever.

It has a large pink with blue trace wire and a large black with yellow trace wire.

It sits just above the drivers footwell junction box.

Traced them back with the multimeter and the black/yellow is part if the Ign1 circuit. The pink/blue is more interesting. It is spliced into the blue/red which is the Acc wire. This splicing has been done in the manner that the factory does it and taped factory so definitely not aftermarket. Both wires supplying the plug I am interested in are the same size as the wires from the ignition (i.e. big).

Both parent wires feed the various fuses so presumably the plug feeds an accessory of some sort. Possibilities include foglights, power windows or cruise control? Can't think of anything else likely. Not power mirrors as that circuit is there as well and already identified. Have looked through the US electrical wiring diagram book and whilst realising that US looms a very different, neither power windows or cruise control look at all likely.

My Euro EWD book is 1983 so pre foglights. I would have imagined that if it was foglights, there would be a link to the lighting circuit so they would only be on when the headlights are on.

Anyone have an idea, especially anyone with a JDM AE86?

[Mos]

It might be a diode.
Originally I thought it's a capacitor, but then it doesn't fit with the pink/blue idea (if it was white/black it could be capacitor). The black bit doens't look like a cap/cover.
If it is indeed a diode, one would need to think of why it would be there... maybe for some reason they want to feed the accessory line when the ignition is on (ie when cranking).

I vaguely remember seeing some diodes on the JDM trueno looms but I can't remember what they did.

Does measuring resistance/continuity across the terminals of the black thing give you anything? Does the black thing have terminals?

Mos.

[parrot]

Yes you're right about the diode, and they are part of the idle up circuit. Unfortunately that isn't what i am trying to identify though. The plug of interest is the white one with the black/yellow & pink/blue (can only see pink in photo) wires.

Have been going through my 1988 Toyota wiring diagram book but the wiring colour schemes had all changed from the 1985 ish era. Though certainly anything which had foglights did not feed from either the Ign or Acc circuit, so doubt it is them.

Shall keep hunting. If anyone has the later wiring loom book (Japan only I think, and on CD from a guy on yahoo japan) please let me know.

[Mos]

Oh, sorry, I was looking at "plug" closest to the camera...
The other plug could very well just be a random supply, maybe even for something like power windows, or central locking (as you say). Some versions (if not all) of the AE92 have a separate loom for central locking, with only the smallest number of wires connecting to the chassis loom.

What's the area of concern though? Just would like to know what it is? Or you're concerned you may be missing something?
There are plenty of unused plugs in virtually every loom that I've come across. You've identified what's on it which is the important part. If there's nothing plugged into it, it doesn't really matter....?

Mos.

[parrot]

Thanks Mos, I appreciate your input.

My feeling is that it is some sort of random supply as you suggest. I'm not worried that I am 'missing' something, rather that I may be 'missing out' on something so to speak.

My big hope was that it was foglight related to simplify a 'factory' connection but that looks extremely unlikely. I have the foglights and the switch, so really all I needed is the option section of loom to do it factory (to me that is important).

Essentially if there is some other option I can easily connect up then I would probably do it, either now or sometime in the future.

When I eventually work it out, shall post it up.

[Mos]

No worries. None of the AE86 looms that I have come across had factory foglight wiring in them, so I can't comment at all on their factory appearance.. sorry..

However, I will make a comment on factory headlight and foglight wiring (I think I'm well qualified to do that )
Factory wiring for headlights truly sucks. They run far too much cabling than necessary, to save a few $ on relays. There is no better mod that you can do to headlight wiring than to run direct supplies to the filaments from as close to the battery or alternator terminal as you can, and short ground leads.

The factory foglight wiring that I have seen (ST185) runs too much wiring as well - supply comes in from the fusebox to the passenger side footwell to the relay, only to travel back to the front of the car - this is far from ideal. None of this wiring is overly thick either.

I would suggest that you concentrate your effort on making the loom for the foglights (and headlights while you're at it ) rather than looking for the factory part - with a little bit of effort you can make it better than factory electrically, and as good as factory in appearance... but then I don't understand why it's important that you have the factory piece, so there may be a perfectly valid reason for it.

JMO

Mos.

[thanhngo]

I have a JDM Dash harness with factory fog light connector + the original switch as well. Here is my one



It has two green wires at the top and one red one. It doesn't look the same as yours? So maybe its not a factory fog light at least...

I can't see any connectors near there with black and pink colour. Will look tommorow morning when their is more light.

[thanhngo]

I have the same connector as yours but its not connected to anything - however my car isn't running yet so I wouldn't know what it is. Sorry.

[kingmick]

I had a very similar supply of a frontcut years ago that went to a strange setup for the brake lights, it had a box that made the brake lights to disco shit and was ajustable.
Id just work of the basic loom and see whats not working, as it is an extra supply not a factory supply.