I have done some searches, and been unable to find an answer.

I have two 2009 Cobalts (see sig below), one SS coupe, one SS sedan.

I have observed that the two cars function a little different when it comes to chimes, and have been unable to find where to change settings to make the two function the same.

The sedan seems to chime less than the coupe;
The coupe was built several months after the sedan - and my guess is that they were setup different from the factory.

The sedan DOES chime if I drive with out my seatbelt on, but recently, I learned that this times out, and stops;
The sedan DOES chime if the key fully in the ignition with the car turned off, and door opened;
The sedan DOES chime when I hit the lock button before closing the door (this is a setting).

The sedan does NOT chime to warn me that the lights are on when the ignition is off and door is open.

That right there is a biggie;
Last summer my daughter turned on the lights, and it drained the battery because I didn’t know she turned on the lights.

Can someone please help me figure out how to fix this - or where any nested setting is to turn this chime back on?

 

My coupe is the same way as you describe, however I made it like that on purpose. It's the wiring for the radio - if you replaced the head unit, you needed the PAC module to retain the steering wheel controls and the chimes for the additional "notifications", especially for that last line. I even kept the blinker sounds off.

 

when I got the sedan it had an aftermarket stereo;
I replaced it ALL with factory correct pieces; including a correct radio from another ‘09 SS I parted years ago;
I used my tech2 to unlock it and it functions properly.

The steering wheel controls all function as they should.

Chimes DO work, but it’s just this “lights on” warning that doesn’t function at all.

 

if you replaced the head unit, you needed the PAC module to retain the steering wheel controls and the chimes for the additional "notifications", especially for that last line. I even kept the blinker sounds off.

 

Please show what the PAC module looks like;
I thought I had all the Tech2 components.

This car does some weird things, but like I said before, everything works as it should, except for the headlight chime.

The radio in the car is the original RPO unit for this car, removed from another 2009 Cobalt.