I have found that the fob has an incredible range. I was inside a restaurant and could see the DJ probably 30 spaces down the row plus the traffic lanes and was able to lock and unlock from that distance.

 

Another thing to bear in mind with the fob and proximity. When the fob is "within range" the car is in a "ready for anything mode"; i.e., power to a lot devices and controllers. I used to hang my keys next to the front door that leads to the car. Didn't drive it for a week and half or so (I have a RAM Longhorn and a couple of antiques) and then one day I went outside to run into town and decided to take the DJ. Battery deader than a door nail... All of those items drained the battery dead. Charged the battery and took it to the dealer for a warranty check of the system and all was good to go - nothing wrong with the car. Started talking to the guys and they informed me what the probable reason for the dead battery was; proximity of the fob keeping the DJ from going into sleep mode. Started keeping the keys in the bedroom at the other end of the house...no more issues. They said normal use keeps the system charged, but, for us (retired and living in the boonies), with infrequent use, it would be best to keep the fob far enough away that the unit goes to sleep instead of sitting in standby for days on end.

Know all the guys at the dealership well (have bought numerous vehicles from them) and while we were having that discussion we got to talking about our RV trips. A month long trip is short for when we go and three to four months is more a "normal" length. They warned me that in no way would the system stay charged for that length of time without putting the vehicle in "Transport Mode" or having a trickle charger attached. They said that for transport from the factory and for sitting on the lot, there is a "Transport Mode" that shuts a lot of those things down so that the battery stays viable - and the "viable" range of the battery without using the Transport Mode was somewhere between two and three weeks, and that is provided the vehicle is in sleep mode, certainly not more than a month. I had them show me how to put it into Transport Mode, but, it was easier for me to just hardwire a plug connection for my BatteryMinder to use for long periods of sitting without use.

 

That's interesting, never would have thought about that issue either.

 

Yes it keeps the BCM (body control module) live.
One poster on another forum was in the habit of throwing
her keys under the floor mat in her GM as it was locked in a secure
garage took multiple trips to dealer until she told them of habit.

 

I'm not sure what the deal was, but I haven't been able to replicate the issue. I think I might be crazy.

 

Same here.