Mystery turn signal plug?

[GDII]

I'm trying to figure out what this plug is for down behind the panel where the fog light switch is.
It's a yellow clear plastic plug with 5 large pins, 2 pins have green w/yellow and 2 pins have white w/black and the 5th pin is empty. It connects up to the power wires and ground wires of the turn signal circuit but I have no idea what is is for.
3 of the 4 wires (2 white 1 green) earth to the body and also appear to connect to the wires in the warning light plug and the turn signal lights in the gauges.




The USDM wiring diagram has no reference to this plug however the same plug with different wires is for the fog lights. This is doing my head in as all the unused plugs I have found I know what they are for.

[Alsw20]

Turning fog lights?

Do your's work?

[GDII]

It's not for fog lights on my car. The fog light switch has 3 positions, up on and turning, middle off and down on no turning. Mine do operate as they should.
I mentioned fog lights because the LHD cars seem to use the same plastic plug but completely different wires and circuit as seen here and in the USDM wiring diagram.

[rocco26]

Could be the connector for dash light dimmer.

[GDII]

That's what I was hoping it was so I went searching but sadly it's not. This would have a 3 pin plug arranged in a triangle configuration and have a green, a white w/black and a green w/red wire. Plus the circuit it's connected to is the turn signals only.

[Alsw20]

Maybe it's like the Nissans of the '90s where when you indicated and turned left, your left fog light would illuminate in the turn, and the same with your right fog light turning right.

[JasonFriday13]

I don't remember seeing a plug like that on my car, obviously the white/black stripe wires are grounds. I would say it's for some sort of accessory that adds something extra to the turning signals, it appears to be an output, not an input.

Or I could be talking rubbish, who knows?

One way to check is to set a multimeter to 12V, connect between a ground and a green wire, and start turning stuff on and off until something shows up on the multimeter.

[Benckj]

Factory alarm?

[GDII]

Ok, thanks to Jasons suggestion I tested voltage readings when turning stuff on.

When turning on the parking lights i'm getting 11v between the green w/yellow and white w/black wires. The green w/yellow wire I wasn't getting a ground signal or any other signal to powers up 11v too.

When turning on the turn signals or warning lights I'm getting a reading of 23mV that fluctuates with the on off of the lights.

Fog lights don't affect anything except a small voltage drop due to load on the battery with the car off.

[JasonFriday13]

Well, the obvious answer is that it's a dash light circuit. 23mV is nothing to worry about, often tiny voltages like that are due to voltage leaking from other circuits connected to the same wire.

What I mean by voltage leaking is that the wire is connected to components that always draw power (with respect to the key position), and some of that voltage will take the path of least resistance to ground. Most of the time it's through it's own circuitry, but it does happen going through another circuit connected to the same wire.

A much harder version to fix is called backfeeding, generally this only happens when a circuit gets it's power from more than one source. Car companies prevent backfeeding by designing circuits to take a single power supply, and using a relay (usually operated off the key) to help isolate it from the battery voltage (which is constantly 12V).

[GDII]

I'm not worried about the 23mV, just posting up the information I found. What's odd though is I'm getting a fluctuating signal on both green wires with the turn signals with no lights on even though I can't find the connection to one green wire.

3 of the 4 pins connect to 80% of the wires in the warning light plug. I clearly don't understand this circuit very well.

Now the question is, what is it mean to be powering/illuminating and why are there 2 power and ground sources?

[JasonFriday13]

It's quite common to wire all the grounds to a single point, this stops potential humming from having grounds going all over the place (this better relates to audio amplifier earthing).

Perhaps it's a combination plug. Power for the back light, and a switch for ... something, who knows?