I was thinking of adding an amp and sub in my 05 LS and i was cleaning out my truck and i noticed an electrical box under the rear driver side seat. it has a large red cable coming in and is mounted with an eylet... can i hook up the power cable for my amp here or not? What is this for?

This is the BCM, I don't think this is a good spot to fool with.

This is the BCM, I don't think this is a good spot to fool with.

BCM??? What is this??? It is still a power wire coming in though, right? I guess i dont understand...

This the body control computer, I would not connect accesories so close to a sensitive component such as this, there are open ports in the under hood distr. box.

where is the best place to run a wire through the firewall???

I drilled a hole in the firewall, careful as to location and used a rubber grommet. l/s of steering column.

i've seen many people install an amp to it without problems, as long as its not too big on one. Check this out: http://forums.trailvoy.com/showthread.php?t=3598

From what Ive read, you can install an amp up to about 500watts to the rear seat terminal on the BCM (Body Control Module). Anything higher, and you are probably asking for trouble.

I wouldn't think it'd be a good idea. The BCM likes nice, clean power. An amp wired here would cause voltage fluctuations. If you run a wire thru the firewall, USE A GROMMET!!!

I have an '05 TB and I have a 400 watt amp wired to the box under the back seat rather than running the wire all the way up threw the firewall to the battery. Wired it to the big 12volt in stud and used an inline fuse about 4 - 5 inches away from the box. Been this way for year a month and have had no problems.