OEM access cab subwoofer power wire

Which wire on the oem stereo harness of my 2011 Tacoma provides power to the oem access cab subwoofer? I have an Alpine 194bt head unit and it works fine until I install the

$163 ktp445a KTP-445A - alpine 4-channel 45W RMS X 4 at 4-ohms amplifier

ktp445a power pack. I am thinking that the harnesses that came with the power pack do not account for the power to the oem rear subwoofer. When the power pack is installed, the rear headliner speakers still work, but the subwoofer does not power on.

From my understanding the subwoofer gets its audio feed from the rear speaker wires so the issue I have now is running power to the rear subwoofer. I could run a seperate power wire from the subwoofer itself, but wanted to see if I can run a shorter wire from the harness at the back of the head unit instead.

 

I know you said you have the OEM subwoofer in your access cab. I'm not sure, but it may require two power wires, one continuous 12vdc and one switched by the ignition key. That's the way the KSC-SW11 that I just installed in my 2009 access cab is wired. I had to run wires up to the dash for mine, since I don't think my truck had a factory harness for the sub. If I had to guess (and it's only a guess) the continuous 12vdc wire will be yellow, and the switched one will be red. You should be able to check it out with a voltmeter or a test light.

 

I eventually found a diagram for the oem connector at the subwoofer. It seems like you are correct about the two power sources, one acc and one ign. I haven't had a chance to test it out yet, but I will run the two power wires back up to the fuse box.

 

Gonna ask an absolutely stupid question.. If the truck has an oem sub, where is it?

I've got a TRD Sport Access Cab (2013 model) with touchscreen but didn't think it had anything other than door and ceiling speakers as a fairly conventional setup.

Granted when I do my install, I'll be completely gutting it for deadening, and all new wiring etc.

 

http://www.autotrends.org/images/x-runner-005.jpg

 

Thanks.. And Shoooooo!

 

I gave up on it and ordered a

$300 kicker 11hs8 8" 150W hideaway car audio powered subwoofer sub enclosure HS8

kicker 11hs8.