donbrew

Why not get the GMLAN adapter? The amp really has nothing to do with the chimes, they are generated by the BCM.

I guess you wanted to re engineer what was done years ago and can be bought of the shelf.

One good source of information and parts is crutchfield.com.

boost8d

I have a GM-LAN-04 adapter from Metra in the car from when I did the install of the Pioneer head unit and everything was working properly until the factory amplifier died. Instead of replacing it I decided to do a whole new setup with new amp, sub, and speakers.

Adding all the new components meant bypassing the factory amp. In talking with Metra's tech support the signal for the chimes goes from the head unit to the amp to the front speakers (it actually goes through the LAN-04 box but you get the idea). So I had to keep the factory amp installed so that I can get the signal to the front tweeter in the stock location for the chimes. I was already running the wires for the RCA from the head unit so I just added one more speaker wire to make the connection and kept my chimes.

donbrew

The chimes come from the BCM to the head unit via serial data, that's what the adapter is for. There is no separate wire to the tweeter, see the diagram above (post #2).

In other words, forget about the factory amp completely, unless you really want 2 amps.

Did I go to that trouble for nought?