Thread: FACTORY MONSOON WIRING DIAGRAM for Audio system Install using LOC

Ive been all over the net looking for the factory monsoon system diagram. Im trying to connect LOC (line output converter) to the rear speakers in my 07 GP GT. But i could not find the diagram anywhere and the proper wiring color codes. This is now in the past as I have found and sharing with anyone who needs it (anyone with a Monsoon factory system, on-star, etc. will).

The proper procedure: Take your LOC and connect two of the wires to the left speaker (Audio Amp C2) using 5,6 (Yellow and brown) and for the right 7,8 (light blue, dark blue). Once connected plug up some RCA jacks to the LOC and the other end to your system. Then for switched12v remote use Audio Amp C1 the number 6 pink wire. And for the power and ground use the cars power as usual cause if you try to use the ones from the monsoon amp it will be to much power drawn, so run your power wire from amp to the battery and ground wire to the chassis (bolt down good!).

Factory Monsoon wiring diagram? - Hummer Forums - Enthusiast Forum for Hummer Owners

Audio Amp C1
1-TN-Left Front Low Level Audio Signal (+)
2-D.GN-Left Front Low Level Audio Signal (-)
3-D.GN/WH-Left Rear Low Level Audio Signal (-)
4-BN-Left Rear Low Level Audio Signal (+)
5-OG-Radio Mute Signal
6-PK-Radio On Signal
7-Not Used
8-GY/BK-Remote Amp Sense Line Signal
9-OG/BK-Right Front Low Level Audio Signal (-) / D.BU in early models
10-L.GN-Right Front Low Level Audio Signal (+)
11-D.BU-Right Rear Low Level Audio Signal (+) / OG/BK in early models
12-BK-Right Rear Low Level Audio Signal (-)
13 to 16-Not Used


Audio Amp C2
1-BK-Left Front Tweeter Speaker Output (+)
2-YE-Left Front Tweeter Speaker Output (-)
3-L.GN-Right Front Tweeter Speaker Output (+)
4-PU-Right Front Tweeter Speaker Output (-)
5-YE-Left Rear Speaker Output (-)
6-BN-Left Rear Speaker Output (+)
7-L.BU-Right Rear Speaker Output (-)
8-D.BU-Left Rear Speaker Output (+)
9 to 12-Not Used
13-L.GN-Right Front Speaker Output (+)
14-D.GN-Right Front Speaker Output (-)
15-TN-Left Front Speaker Output (+)
16-GY-Left Front Speaker Output (-)


Audio Amp C3
1-OG-Battery Positive Voltage
2-BK/WH-Ground
3-D.BU/WH-Left Subwoofer Speaker Output (+)
4-L.GN/BK-Left Subwoofer Speaker Output (-)
5 to 6-Not Used
7-L.BU/BK-Right Subwoofer Speaker Output (-)
8-L.BU/BK-Right Subwoofer Speaker Output (+)


On the radio should be a 24-pin connector (2-rows (A and B) of 12)
B1-OG-Battery Positive Voltage [I believe this is constant and not switched]
B3-PK-Radio On Signal (not 12v)
B6-OG-Radio Mute Signal (not 12v)


TOOK ME LONG ENOUGH TO PUT UP MY FIRST POST HERE... Popped my Cherry

Not the pink wire... Its actually purple...

i just installed subs in my 07GTP w/ Monsoon. I hooked them up to the wires you indicated and did not have much bass. So tonight I hooked them to the blue and green wires going into the 6x9 and WOW!!!! My bass is set on negative 3 and it is still too much! So if your hooking up subs hook it up to those wires, otherwise if your hooking up full range speakers use the ones recomended in the post above!

which wires did you use on the blue and green?? all four speaker wires from the LOC???

from the LOC they have 3 pairs of wires (right and left), and a single remote lead... confused on which ones you used and if only used a single pair where did you connect the others??

I hooked the right side to the blue and green and the same on the left. my loc just has a right, left, and optional ground. I did not need the ground so just hooked them into both speakers.. hope that helped.

First post question. I am in the process of adding a JL 13w6v2 and JL 500/1 o my 05 factory monsoon, I know I need a LOC but there are contrasting remarks on here, I have already replaced all my stock speakers with Alpine type S and when doing the rear 6x9's i notice of course the dual wires per speaker, one being a low pass "sub" and the other being a high pass i assume...I only connected the low pass to add more bass while waiting on sub box. Should I swap those out and connect the low pass to the LOC and then connect the high pass back to the 6x9's to had mid and treble? sorry if i have confused.

Also I am running the 13w6v2 @ 2 ohms i assume thats ok? its been 7 years since ive had a system of anytype, so its like starting over

and it says i can run the remote to my 500/1 off the factory amp buy using the pink or purple wire??? i assume i can splice into that on one of the 3 harnesses going into the monsoon amp?

as long as your amp will give you the power you need, but not more than you need for that sub you can wire it at 2 ohms.

for switched12v remote use Audio Amp C1 the number 6 pink wire.

where is that located?

If I forget, bug me to take a picture.

It sounds like it depends on the year of your car which wire to hook up for your remote. You can always run a wire from your fuse box that is switched.

Hey guys I realize this thread is over a year old but Im having a lot of trouble getting my sub to work! I looked all over the web and finally found this post and thought my troubles had ended, but of course i was wrong! Ok so I have a LOC that has 4 wires coming from my LOC, its a scosche LOC and the installation directions say that I need to hook up the wires to a positive and a neg speaker wires. I do not have a ground wire on it just wires to connect to the speaker wires. so I hooked up all my wires just as Ivory said to and I had no luck with my sub working. I know my amp works because its been tested. Chillery said he hooked up to a blue and green wires but which ones? Some people say that they hooked up to the "low level" wires. Any help would be great!

Thanks for the article! I just hooked up a bandpass sub in my 06 Grand Prix Special Edition with the monsoon sound system and used the wires you suggested. Everything went great. The purple wire wouldn't turn the amp on for some reason, so I wired it in the moon roof fuse and it works perfect...thanks again!