I have a car that has an aftermarket head unit installed. It doe not seem to be connected properly to all of the original speakers as it sound terrible.
If I put an original type unit back in, does it have to be programmed to the car to work?
Thanks

 

don't think there is any programming required but do you know if the original system was standard audio or premium? Premium will have small triangular speaker grills (Alpine) on the door/window frame. If they left the amp installed when they updated the head unit - may not be compatible

 

Did your car have an amp in the trunk? how did you deliver signal to the speakers?
I assume your after market stereo is 4 ohm. The speakers in these cars are 2 ohm IIRC.

So yeah, a fair bit to unpack. When going aftermarket, I recommend completely bypassing the OEM amp and replacing the (IMO crappy) paper 2ohm speakers with aftermarket 4 ohm pieces that are going to sound massively better. Even cheap rockford fosgates and a cheap blaupunkt amp sounded way better than the stock audio I had before.

 

This car had a premium system with the amp. I am not sure what is left of it yet

 

In the 'vert, the subwoofers are cheap paper 2 ohm units. The door speakers are cheap, paper, 4 ohm units. Upgrading the speakers didn't seem to make a ton of difference. I did all of mine and it's better, but not WAY better. Only mid-range frequencies go to the door speakers, and only the low bass freqs go to the rear subs. The crossover is built into the factory amp. The system was designed to have most of the sound coming at you from in front of you, at least in the 'vert. I understand the coupe has regular speakers and a sub in the back. Lucky them!

I'd love to change out the factory amp and head unit at some point, but then you lose the CD player (not the end of the world), and the Nav system, and the cassette player (OMG) and the steering wheel controls (unless you get an adapter kit). I'm tired of throwing money at this thing, so I think I'll live with the stock limitations for a while longer.