2002 Yukon Xl 2500. New battery, dead in 5 days of sitting. Assuming it is a key-off drain.Recharging with trickle charger produces clicking and popping noises from dash area and console. Sounds like a CD ejector going on and off too. Can jump start no problem. Other than going on an Easter Egg hunt with voltmeter and pulling fuses any ideas?

Are you certain the battery is draining after key off?? Have you had the charging system checked? Alternator?

Battery is brand new and has been tested. Charging system, alternator and starter have been tested. All check out fine. So the alternative is a key-off drain in my notion.

Check to see if you rear fan blower is turning off when you shut the truck off. Ours were staying on even when we turned them off and it was draining the battery.

What ended up being the problem? Si.ilar situation with a 04 yukon xl in the cold weather

I had the same problem, the positive battery cable that goes to the alternator gets rusty inside. It cost like $14 and took me 15 minutes.

I had the same issue and what I found it was if turn the key too far backwards, it seems to activate OnStar. When you pull it out while your door is openb you will hear a dinging notification. If you turn it forward one click and then pull it out (while your door is open), you will no longer hear any dinging notification, just silence which is what you want.