2015 Grand Caravan, Value Package, 104K km
As I recall, normal operation is this:
-Turn off the vehicle.
-Remove the key from the ignition.
-After a time delay, the backlight to the buttons on the centre console go off.
-Air control actuators perform cycle.
Malfunction observed:
-Turn off the vehicle.
-Remove the key from the ignition.
-The backlight to the buttons on the center console remain on.
-Air control actuators perform cycles at intervals.
I have recently replaced the seven-year-old battery. Just before making this post, I disconnected the battery to allow for the computer to do a reset.
I expect after the computer reset, that problem will persist, as observed by backlight on continuously on the center console buttons. (ECON, Trackion Control, Hazzard Switch)

 

Disconnect the battery to allow for the computer to do a reset.
Resolved the issue.
If a door, i.e. when passenger sliding door, is opened when the van is locked, or not, the "backlight" is activated on the console switches. After a delay time, the backlight goes out. This was not happening before. The backlight was on continuous. Appears to be triggered by door switches, locked or not locked does not change the timer turning off the backlight of the dash switches.

 

Solution found. Backlight glow, caused by cycling of occupancy sensors. If you leave something on either of the two front seats, you may cycle the detection. Realizing that the back glow was not there, I place tonight on the driver seat. Immediately the back glow came on. Remove the item from the seat, and a few minutes later the back glow turned off. Research online revealed that the bottom seat cushion has a switch embedded near the front edge. Both the driver and passenger seats. The electronics for this occupant detection is under the passenger seat near the front toward the center console.If you want to stop the drain on your battery, don't leave things on either of the two front seats. The circuit will continue to cycle and deplete your battery.