pentavolvo

yeah its all the same

TheKomoman

For the purpose of this discussion, negative = ground.

BigButtLover

Thanks. I'm picking up some tomorrow and start working on my adapter.

BigButtLover

Could I use the PAC AMP-RCA and omit all the soldering? Thanks.

TheKomoman

The connector on the end of that pigtail is for the other side of the OEM-1 box that the ADD-GM24 is designed to connect to, and that we're eliminating from the equation. You could use this yes, but you'd have to clip the molex off and splice the wires together from the ADD-GM24.

BigButtLover

Thanks.

ProgGod

any chance in fixing the pictures?

pentavolvo

which pics?

TheKomoman

Yeah, they're fixed, had some thunderstorms rolls through here last night and it took out the ethernet port my web server runs on. Should be back up and running.

VETTE-NV

I've upgraded from my stock Bose sound system with an Alpine PDX-5 amp and some Alpine component speakers and I want to keep the stock NAV head unit. I made the harness using the GM-ADD24 as shown, but the system would simply not function. My installer checked out the amp and speakers and they are all working properly. Basically, the stock HU would not even power up and turn on.

Just to double check, the GM-ADD24 is plugged into the back of the head unit, and the stock HU harness then plugs into the new harness, correct? Any ideas about what I've done wrong?

I've just ordered a complete new harness including the OEM-1 black box just to double check without having to splice anything...should be plug and play, plus that's about the only way to get a new GM-ADD24 harness since they are back ordered.

Ol'55

Dan? Please excuse my ignorance on this subject, but doesn't the PAC AOEM-GM24 do the same thing and is sold as a unit? (Best Buy $36). I'll be adding an AMP to our newly acquired C6Z car with OEM Denso touch screen Nav/Bose/Bluetooth/XM etc. with new door speakers and sub, but I would like to retain the factory Head Unit. Gathering parts as we speak. Thanks for your and Kale's help with the C5 last Spring.

VETTE-NV

Got the new harness including the OEM-1 black box. Hooked it up and everything now sounds great. Not sure why the first harness didn't work.

I never thought I could get sound this good using a factory head unit. The Subthump enclosures fit perfectly and hit hard, but I think the 10" Bose door subs that I replaced with an Alpine 6.5" sub and 1" tweeter component system actually had more base. Overall, though, the car finally sounds incredible and I still have the functionality of the NAV head unit. The Alpine PDX-5 amp has tremendous power....and no more muddy sound quality. Killer base and crisp highs.

ROC OUT

Here's a dumb question: What do the white and grey plugs on the pac add-gm24 harness plug into? I been reading this and other threads and can't seem to find the answer. I just bought one and am planning the install and have to figure this out. Thanks.

CGZO6

One is a perfect match for the stock harness that plugs into the stock HU (dark grey with blue tab). The other is a match for the outlet in the HU that the stock harness plugs into. You unplug the stock harness from the stock HU, plug the adapter into the HU, plug the stock harness into the adapter. The third smaller white plug is the output to the aftermarket amp.

ROC OUT

Thank you! That is exactly what I needed to know.

morris

So am I correct in understanding that with this you are left with a set of front speakers and you have to use the rear outputs for the sub? Which means that the existing rear speakers are no longer used...

TheKomoman

That's the way most folks do it, yep. However you do still have the option of leaving the rear speakers connected to the OEM system (the ADD-GM24 is a pass-through so it doesn't disable anything) if you really do want rear speakers. Most folks find that in a cabin as small as a Vette's they're not necessary, but it's entirely a question of personal taste.

LT Ed

Good write-up, looking to upgrade my stock system soon using the OEM HU. I have a JL 300/4 and 500/1 but I just want something better than stock plus I like the OEM look. Thinking of the PDX 5 channel or 4 channel with a strong front stage and a stealth sub fitted somewhere in the rear.

Bradl1982

That's what I did, just spliced the wires together and soldered it. No need to buy extra parts.

Lomison

I wired up the harness exactly as described...triple checked that everything was soldered up well and nothing was touching. When I plug the rca jack into my amp I get a strong high pitch tone through all the speakers...not just the subs hooked up to the new amp. Any ideas what could be going on? I have the basic (non-Bose) stereo. I was trying to hook up an external amp and two subs.