Sometimes once 11 GMC Sierra is parked and engine is off I get 3 slow chimes once driver side door is opened. It's not the same fast repeating chimes when the key is left in egnition. I get no info on the DIC since all electronics are off. It seems to only happen during the day. I don't think it's from leaving any lights on (head lights or cabin). I can't think of any reason for this.
Any thoughts?