02 Olds Intrigue Mirror Wires

I am trying to install an auto dimming mirror in my Intrigue. There are currently 4 wires connected to the original mirror (non dimming - just has map lights). I am needing to find what the wires are for, so I can connect the new mirror usuing the exsisitng wires...thanks for your help!!

power, ground, door trigger and something else. The something else may be an illumination wire...which would mean it will show power when you turn the headlights on. Test them with a meter.

Typical GM colors are as follows, BUT, before splicing into any existing automotive wiring, you should posess some sort of meter or at least a test light, and have the knowledge of how to use it.......you REALLY, REALLY want to test these wires and make sure they do what they're supposed to. Orange: constant power Black: constant ground White: domelight (ground when domelight is on or door is open) Light Green: backup lamps.....GM cars with auto-dimming mirros will have a backup lamp wire, so that the mirror can revert to full brightness when backing up (positive while in reverse) If the fourth wire isn't backup lights, it might be some sort of pre-installed provision for OnStar or a compass, even if your car doesn't have those features.