2010 Prius Fog Light Install [Retrofit]

Correct.

Correct again. There was little cross of instruction from the text I used to create the document from. The other author was installing the OEM light stalk and was using more of the existing wires.

Hmmm. The red wire from the pictured harness I am pretty sure should go to the lamp harness. I am thinking now the yellow / blue should be power from the fuse box. The green should tap the brown wire from the ECU.
Again, it shouldn't be hard to hook up that switch harness and test it out before you put it in the car to make sure. The relay should click when you switch it on / off and you should get 12v from the red wire. Also it the switch is lighted, the lamp will go on if correctly hooked up.
Remember I am just guessing here since I don't have a wiring diagram. So best not to hook it up to the car (the brown wire) until you are sure.

 

[delete] duplicate.

 

Yes, I ran two wires through; one from the fuse box (white in my case) and one to the lamp harness (red in my case). It was tight but used a little lube to get em through.
I am just conveying my wiring solution. Others tapped into one of the parking light wires under the hood and didn't even use a switch. There were a few variations.
To test this, I would simply hook up the black to the battery (-), the blue/yellow to (+) and a meter to the red. Tap the green to (+) and you should hear a click from the relay and get 12v from the meter.

 

Not sure what you are asking but the way I described the wiring in the document, will work on any Prius 2010 model. The model V is the only one that comes with factory fogs and thus the complete wiring. Others here bought the factory light stalk and used existing harness as much as they could but were still never able to get the dash fog light indicator to come on. In other words, I do not believe there is enough wiring harness in your car to do what they did in that link/post you provided.
I tried to keep the install as simple as possible.

 

OK, good job tapping the brown wire!

Again I would pop the hood, attach the switch harness to the lamp harness. Attach the ground to the car body, attach the yellow/blue white to the tap inside the fuse box and then also brush the green wire to the same tap with the car powered up. All this should happen under the hood (don't worry about the brown wire inside the cab).
If that does not turn on the lamps, exchange the yellow/blue with the red wire.
If that doesn't work, check the fuse in the switch harness to make sure that hasn't blown.
Did you say that you had a volt meter or not?

 

As far as pin "18" (I think the instruction say "#8") don't worry about that. That was from the guy that was using the wiring from the OEM light stalk. I should better clarify that in the document.

 

Right, your harness does not have a fuse like mine did. I suspect that this unit fits more precisely into the Yaris than did mine. E.g. it uses the Yaris fuses.

I was just thinking on checking 1. the voltage from the car (the fuse box) to make sure you had 12v there and 2. to check the voltage at the relay if any.
Could you take a close up photo of the wiring @ the relay and the wires at the switch? I need to be able to tell the colors of them.

 

OK, from the photos I stand by my last suggestion:
Blue/Yellow - 12v in (from under hood fusebox connection).
Red - 12v out (to the lamp harness).
Black - ground.
Green - 12v in (brown wire ECU).

When you get a meter,
1. check that you have 12v coming from the brown wire when the parking lights are on.
2. check that you have 12v coming from the tap inside the fuse box when the car is powered up.

3. with the switch harness hooked up, switch in the on position, check to see if you have 12v coming from the red wire.

Also check to see if the lamp harness ground wire is connected to the car frame.

Let me know...

 

Praise the Lord! Phew, I was beginning to wonder if you had a bad switch harness.
Yeah, let me know how things go. I lost lots of skin running the wires. To reduce it to one, you could find a high power 12v source inside the dash area (for the yellow/blue wire). I didn't want to mess with that myself though... didn't want to take chance of messing an ECU.

 

I am sooo glad it is working now. I didn't realize that you were installing HIDs.
There is instructions in the document on aiming the lights. Went well for me. I just placed a large piece of cardboard in front of the car about 5' I think and measured up from the ground. You should be able to fit a ling Philips head screwdriver from the underside of the car into the knob-looking adjuster and twist. It was tough to get started but once loose, it moved fine.