Fog Light Install w/ OEM Turn Signal Stalk / Switch

You would have to power your foglights from the relay's output terminal - not a random power source. Do you understand how relays work? If you can locate the relay, you might be able to identify the output with a test light and there might even be output wires already in place.

 

Why start a new thread?

 

If you can find the foglight relay's output terminal/wires you can "probably" snip the wires in the harness you are buying and attach the leads from the foglight units to the relay discarding the rest of the harness and the switch and relay that came with the harness.

 

In my 2010 liftback, the relay is present and has a power source, there just isn't any wire for that pin in the wiring harness that runs through the firewall. Just a matter of running a wire through the firewall (ugh), then putting the right repair terminals on each end to fit in the unused positions of the connectors (one, the connector to the Body ECU, the other, the connector junction between the engine compartment harness and the bumper harness with the fog connectors. The wiring diagram shows clearly which pins to use at each end, and (if you click the "Wire Harness Repair" link) shows the part numbers of the repair terminals involved.

-Chap

 

Has anyone done a similar fog light installation recently? My friend and I have had a devil of a time trying to work out the wiring situation.

I already installed the replacement turn signal stalk--fog relay clicks on audibly and dash indicator lights up with its use.

But tapping into whatever power that makes available is proving impossible.
We have a kit that's designed to be used with an aftermarket dash switch, with the intent to remove the extraneous parts of the wiring once we're sure.
Just to test before going through the trouble of going through the firewall, we tried hooking the ground up under the hood and running the power wire into that terminal repair kit pin 82998-24350 into position 8 on 2C. But the bulb we had to test would not light up (bulb was tested separately and is good). So the power is not being delivered from there? But the power must be coming from that apparatus inside somehow since the fog light fuse is located there, correct?

Or, assuming for manufacturing simplicity there is already some wiring to provide the power running under the hood we need to tap into, where the hell is it? 98% of the guides we can find for this involve the damn dash switch kits. It's positively ludicrous that kits for doing it this way aren't a thing, because removing the steering wheel for the turn signal stalk was pretty easy, all things considered, and looks and operates so much more cleanly.

 

Do you hear a click from the relay inside there when you turn the stalk fog switch on and off?

Bear in mind that will only happen when the headlights are turned on, and only for low beams.

 

Yes, with my low beams on, there is a very audible "click" ~half a second after turning the fog switch on. It's just finding where that power is being provided that's messing with us. Feels like 3 people on the internet have installed this this way rather than with the dash switches included with the kit, but I really want to make this look and feel factory-like.

 

Well, the Instrument Panel Junction Block "inner circuit" diagram for 2010 clearly shows where the power comes out. As long as there's a fuse installed in the FR FOG slot, you can use either 2C-7 or 2C-8 (or both) to harvest the power. In my 2010 it was exactly that simple.



I suppose Toyota, at the factory, might use both output pins for more current capacity. Because I added LED fogs, I just used 2C-8, and replaced the 15 amp fuse with a 3 amp.

Everything I've seen for the v suggested the pinouts hadn't changed, but I don't have the v diagram in front of me to look at. If there's any question, get a 2012 v diagram and see what that shows.

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