C6 08 non-bose factory radio. I am installing new NAV head unit.

I have the GMAH24 and want to connect using the factory amp to power front speakers and NAV head unit's built-in amp to power rear speakers.

Can I actually do all that with just the GMAH24? It seems that I CAN connect the front speakers from the factory amp speaker output to the GMAH24 and the use the NAV's amp directly to power the rear speakers.

As far as the speaker wiring is concerned, is the GMAH24 just a pass through wire connector? And it's not really needed if I dont use Onstar? So I can connect my speakers and amps any way I want - am I correct?

Is the GM factory radio connected with RCA jacks to the GM factory amplifier?

Where is the factory 12 pin harness and 24 pin harness connectors located? And where is the factory amp? Also anyone know what is the wattage output of the factory amp?

Thanks so much for your help!

 

u lost me like 5x over there

if u want to bypass the factory amp for ur rear speakers u need to run new wires to speakers or tap in at the amp and not use the wires in the gmah24

 

I'll answer these the best I can....

You could run the speakers the way you describe but you'd have to run new speaker wires to the rear. I don't know that an amp built-in to a head unit is significantly better than the factory unit so to my mind not worth it, but to each his own.

The GMAH24 is NOT just a pass-through. It contains a line-level conversion circuit because many factory head units are self-amplified. you do not need to connect the speakers to it if you're going to use the new head's amps or you are installing an aftermarket amp, but you do need it to turn the amp on and to attach a GMAHCM to it so you get chimes. If you decide not to bother with Onstar get the GMCO instead of the GMAH24/GMAHCM combo, you'll save money, time and space.

The factory radio & amp are connected by wire harnesses, not RCA jacks. The signal between them is line-level/RCA but not the connector.

The 12 & 24 wire harnesses plug into the back of the radio and then wires split off. The factory amp is in the passenger footwell. Not certain of the wattage but it's low, something like 12-15W. For anything above a basic pair of coaxial speakers, figure on an aftermarket amp.

One thing as you're considering the wiring setup you're going to use - the crossover network for the factory system is built into the amp, not the head. So if you run new wires for the front speakers to drive it from the head (again, not worth it to my mind) you'll have to rig some sort of a crossover to split the signal between the 3.5 & the 8.

 

Thank you much for your reply...so far you cleared up the factory amp question for me. I wont use it.

So now my options are :
1. Use the Kenwood 8120 output (with no external amp) to drive my speakers front and rear. Replace the rear with 5 1/4" coax and install 3 1/2" coax in the doors and keep the GM factory woofers and use Dynamat. Can I use the GMAH24 and GMAHCM if I use this configuration? The GMCO?

2. Install a component speaker system with a new external amp. Will the external amp fit in the same place as the exist factory amp? I see you installed the same 8120...what did you use? Can I use the GMAH24 and GMAHCM if I use this configuration? The GMCO?

3. I really dont use the ONSTAR (I dont like strangers in my car) - so maybe I'll sell the GMAH24 and GMAHCM modules I already bought. Does the GMCO use a buzzer or a chime? A chime is my preference. Will that unit allow me to use new external amp and/or keep just the Kenwood's amplified speaker output?