View Full Version : How to: Firewall access for 4ga wire

09-14-2016, 02:39 PM
Vehicle: 12 Sky GS Hatch, non-Bose with 6 speed manual.

After much researching, I've found that there were several potential areas to run a 4 gauge power wire as listed below.

1) Below steering shaft. I couldnt get it open enough to even try fitting a large power wire in there. Risk of water leaking in.
2) Using grommet for hood release. a 4ga would probably fill that entire spot
3) Utilizing AC/Heat lines located behind the glove box. I didnt even attempt this. Too risky being close to those lines.
4) Main wire harness behind the wiper motor. I didnt attempt this as i Had already tried 2 others.

Here's my solution:
On the passenger side of the engine bay youll see a circular outline. There is nothing even close to this location. I ended up drilling through this area (full glove box must be removed) from the cabin into the engine bay. I put in my own grommet and sealed the grommet with RTV.

Heres the pics for future reference:

Want to thank? Just comment if this was of assistance :)


09-14-2016, 05:57 PM
Mods can you change the title to include years or generation as to not confuse users

09-14-2016, 07:25 PM
Pretty much you can buy any size grommet that will accommodate the wire you want and then drill a hole to size.
Ideally you would have it slightly lower than the glove box for easy access, and behind the heat pad/mat in the engine bay.