'12 dbl cab; Add 2nd subwoofer outputs to JBL system

I apologize to audiophiles in advance, as I know that what I did here, "ruins" the accuracy of the JBL system, but I wanted BUMP!

I didn't want to remove or add or cut up anything since the truck is brand-new ('12 double cab TRD sport prerunner), so I set my goal to add a larger sub to the existing system, and run it on it's own amp along with the JBL amp and the factory subwoofer. Since there aren't any RCA outputs, I added them to the JBL amp by doing a little reverse-engineering and so forth. I removed the JBL amp & sub assembly, then removed the board from the amp, and connected wires for turn-on, main power, and high-level (speaker outputs) from the JBL amp. I then bought a line level converter, which takes the full power speaker output wires, and converts to 1v RCA audio signal. In my case, I wanted only the subwoofer signal, so I went for the factory subwoofer wires this time. Works great, and can be 100% un-done if needed for warranty purposes! Here is the color code for the subwoofer wire harness: NOTE: this is DIFFERENT from the '11 and older color code, per the schematic I have!

The colors change where the subwoofer is plugged into the body wiring harness below the JBL amp. At the plug coming out of the subwoofer enclosure, this is the code:

RED=L+
YEL=L-
BLK=R+
GRN=R-

At the body wiring harness plug:

GRN-YEL STRIPE=L+
GRN-WHT STRIPE=L-
BLU-BLK STRIPE=R+
PURPLE-RED STRIPE=R-

Again, this is for SUBWOOFER only. If anyone wants to create RCA outputs for full range, they will need to trace out the correct speaker output wires for that purpose.

The amp turn-on signal wire is gray, and is at pin 12 of the larger white plug (if I recall; I forgot to note which plug, but it was the only plug with a gray wire at pin 12).

The 30-amp fused battery-direct 12v power feed is two white wires with blue stripes at pins 1 & 10 of the main plug at the JBL amp, but beware that these should NOT be used to power another amp, as the circuit will overload. Run a new suitable wire with it's own fuse from the battery for that purpose.

DISCLAIMER: I am sharing my own findings, and what I described, would likely legally void any warranty, and could do damage to the Toyota stereo, wiring, or any new components, if things don't go right. I happen to be a qualified electronics tech, and I'd advise anyone who is NOT a qualified or at least an experienced electronics hobbyist, to get a pro to do this. It involves soldering and handling of ESD-sensitive parts, and you need to add heatsink compound to the output chips on the JBL amp if you take the board out as I did, or they can overheat when you put it back together.

Charles

 

excellent write-up. Do you happen to have the schematic for the 2011 and older? I am about to do the same to my truck, time for the jbl sub to go.