What is the black thing in this monte carlo trunk on the left side.

 

That is your OnStar unit

 

Oh ok thanks.

 

yep as stated its the onstar unit

 

If you don't subscribe to onstar, you can unplug and remove it.

 

I did that and they sent me a letter saying they could not local my car..
Letter said take car to GM for repairs , I put the letter in trash can..

 

That could really start some conspiracy theories

 

that's what I thought Big Brother is watching ..

 

the cover wont stay on mine. everytime i open my trunk, its laying off to the side.

 

If you have the original onstar unit in your 2004, like I do, you have the old analogue system. Onstar upgraded to digital about a year or two ago. Making the original analogue unit obsolete.

If it bothers you, and you don't use onstar anyway, unplug it and remove the entire black plastic box. You gain a little bit more storage space on the left side of your trunk. Enough for an extra bag of groceries, or an extra six pack of beer!

Inside your car, one of the LED's on your mirror will go out when you unplug the onstar unit. Other than that, you shouldn't have any issues.

Just becareful for the men in black suits from the government showing up at your car in the night re-installing the onstar unit so they can track you.