eej711

How can i run wire from the battery into the cab to a switch? I know there is a place near the feet of the driver but how difficult is it to run it there or is there a better place to run wire?

dereku

Use a relay to power what ever you want if it is switched and out side. If you need power for something inside tap the fuse box or make a separate fuse box that is relayed to the battery.

eej711

I am going to be doing that with the relay and a switch inside the cab. How do i route a wire through the firewall into the cab to the switch?

$pitt04fx4

Call a specialty shop in your area for advice..use zip ties and keep it away from anything that gets hot or moves, make sure there r no sharp metal edges that will cut into it...as long as it gets there and won't cause issues ur good to go...good luck!

firehose777

there's grommets you can buy, just drill a hole to size, and put the grommet in there to keep water and crap out. I've got several put through my firewall with no problems. don't buy the ones with holes already in them. buy the ones that look like rubber plugs, then make your own hole in the rubber. they seal around the wire tighter and reduce the chance of leaks. I even goop a little silicone around the wire to be extra cautious, but I'm kinda OCD about that kinda stuff.

HeloWrench

You don't even need a grommet. Make the hole small and near the existing wire bundle, but don't hit it. Clean the engine area with rubbing alcohol and throw some red rtv on it. It'll keep it water tight and won't compromise the firewall.

No Thanks

The first step is to find that place in the firewall.

Fish through from the driver's side into the engine compartment with a long pull string to pull your new power wires.
You may need to use a stiff piece of wire or coat hanger to get it through, wrap it in electrical tape.
Pull the wire and string on out.

Understand that you need to work from the end of your new power-ground wire that is not terminated with a connector. so once the pull string is in place you are going one direction or the other
This is either battery to cab or cab to battery.

Manage the wire away from moving parts but bring it straight up from the firewall and work it under the cowl at the top of the firewall.
Get both ends where they need to be.



Red wire direct to Positive.
Black to a good ground. My 2005 has one right near the battery.

Be sure you have an inline fuse on the red wire.

.

YJay90

There's an existing hole/grommet in the firewall above and to the left of the gas pedal. You'll have to pull back the carpet to see it. Route the wire away from anything hot/moving.

firehose777

I've done this on other vehicles, but found that over time the adhesion between the rtv and metal can give out, and the edge can wear on the wire insulation. That's why I always use a grommet, it may add 10 min to your installation time, but it saves from having to make repairs down the road.

'08f150stx

Find an existing grommet. Put some type of wire wrap around the wire and tie wrap it with black wire ties under the hood. Might be a little more work finding the wire inside the cab, but worth it to keep a factory appearance.