Getting wires through the firewall

Have you checked in your Wiring Diagram Manual on techinfo.toyota.com to see whether there is an existing driving light circuit that you could use, possibly by adding a fuse and/or relay that might have been omitted in your model?

-Chap

 

I'd be interested in this as well. I was able to pass through the firewall by following the hood release cable, but that required cutting through the grommet that holds the cable in place.

 

Why not? One option is to get the stalk. If you don't like the price, another option is to find the affected wires (the wiring diagram manual shows their routing, color codes, connector locations, and how to release the terminal-retention mechanism in each type of connector), release the terminals in question from the existing stalk connector and extend them to your own switch on the dash. (I tend to do this by sticking the whole extracted terminal into a barrel-style junction block with my extension wire; keeps everything stock and if I ever want to undo it, the terminal pops right back into the original connector.)

You still end up doing some wiring of your own to your chosen dash-switch location, but you use the existing harness wire that already crosses the firewall, which seems like an elegant solution to your original question.

-Chap

 

I know you're going a different route, but if you're interested I followed these instructions on get through the firewall. It shows the hood release cable path I used to push power for DRLs, forward camera, fogs and radar detector. As of right now that hole is getting cramped so I'm curious if you're able to find an alternate path.

Edit: I forgot to put in the link..
http://www.trdsparks.com/install/00016-47160inst.pdf

 

I tapped into the underhood fuse panel with an add-a-circuit fuse. I used the engine ECU fuse. This one turns on my front LED lights whenever the hybrid system is in ready mode. I have not had any issue with it - but it's still questionable lol. The downside is that the fuse holder is meant for regular AT-mini fuses - and the car uses mini-low profile fuses.

My LED DRLs are in the turn signal housings. They are White/Amber switchback LED bulbs from DDM tuning. They are normally white all the time. When the turn signal comes on, the white switches off, and it flashes amber/off. After a very short delay of the signal going off, the white comes back on.

So the LED DRL looks VERY similar to the top models of the regular Prius, and also the new Camry, but the turn signal function is similar to Audi/Mercedes/Chrysler implementation where the ornamental lighting turns off when the turn signal is on to increase the visibility of the turn signal.

 

I ended up using the heated seats fuse line for mine. I don't have heated seats and it only turned on when the car was on, so it worked out.

 

Scratch that. After looking at the fuse panel in the manual, I probably used the moon roof line. Again I don't have a moon roof. The seat heaters share the same fuse as the AC, so I probably stayed away from it. I'd go out and look in my car to be sure, but it's cold and dark and I'm lazy.
If you're interested, the page I'm referencing is in the do-it-yourself maintenance book, page 54. Shows the fuse panel and what fuse corresponds to what.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjMmIazg9jJAhVD7mMKHe1zDr0QFggpMAA&url=http%3A%2F%2Fwww.toyota.com%2Ft3Portal%2Fdocument%2Fom%2FOM52A87U%2Fpdf%2Fsec_4-3.pdf&usg=AFQjCNHmq_OQTURutm0kHVPnkBVkzr1TNg&bvm=bv.109910813,d.cGc

 

The windshield water line I didn't see, but standing at the front of the car, the hood release cable is behind the front driver side shock. You have to pull aside the plastic protective lining in the wheel well to see where the release cable passes through the firewall.
I could have sworn I linked to it above, but I'm not seeing it on my phone.. But the instructions I followed to get to that hood release path are on page 3 here:
http://www.trdsparks.com/install/00016-47160inst.pdf

 

I use the battery jump junction under the small fuse box under the hood, it reads constant 12v, to power my relay for HID. It's been working great w/o any issue. I guess you can add a fuse in series... Poking a hole in the firewall is PITA.