I have this 2008 Vue and have noticed that the bulbs are missing in the back so I put new ones in and even with the car off and not in R the backup lights come on. I am lost on this one.
I had to pull the bulbs till I figure this out.

 

The online Charm manual (see here) indicates that the backup lights are activated by the backup light switch on the transmission, but the signal goes from there to the PCM to the BCM, and the BCM applies the voltage to light the bulbs. If the bulbs are always lit (when installed) it seems it might be a BCM problem. With everything working properly, the bulbs should not light with the key off.

 

Does anything else share that BCM output?
Maybe a case of wiring shorted to B+ somewhere between the BCM and the bulbs.....?

I suppose the definitive test is checking the output voltage at that pin on the BCM versus ground with the key off. There's either voltage or no voltage......

 

That BCM output feeds the backup lights and the inside rear view mirror (if the autodimming mirror is installed). The mirror also receives power from a separate fuse (ISRVM/RAIN), and I'm guessing this input (shared with the backup lights) tells the mirror that reverse has been selected (to cancel the autodimming while backing up?). I'm just Googling and guessing.

Also just found this in a booklet titled "Getting to know your 2008 Saturn Vue": When exiting the vehicle, the headlamps and reverse lamps will turn on to provide added illumination around the vehicle.

This would definitely be controlled by the BCM, pointing another finger at it as the culprit.

 

Doesn't the damn thing have a camera?
Kind of funny, I owned one and don't remember

 

Can you please post the link to the charm schematic for this, or better yet the image? Will make discussion easier.

 

Charm schematic for inside rear view mirror: inside rear view mirror

Charm schematic for backup lights: backup lights

 

dreinhart, how long did you have the bulbs in before you took them back out? According to post #4 (above), the lights will come on after closing the doors, apparently for a limited time. Maybe 1 to 2 minutes? Try putting one bulb in, closing all the doors, and wait for a couple of minutes to see if it will turn off.

 

Now I didn't think about that I will try it again. I'll put them in and give a little time and see what happens.
When I bought the car and went over it, that is when I noticed the bulbs was missing well taken out of it.

 

I'd give it a max of 5 minutes. If they're still on after 5, I'd suspect something isn't right.