What is going on just after I turn my truck off

[A321Driver]

So the other day I'm sitting in my truck and turn it off as I'm taking care of call.  Then I start hearing all this activity under the dash.  It sounds like bunch of relays cycling and small motors running.   It happens a few minute to several minutes after I turn the vehicle off.

Anyone know what exactly is happening?  I am sure it is normal, just curious

[milkmaster]

My '21 Sierra SLT does that if I turn off the truck and sit inside instead of getting out.  The seat never moves like it does when I open the door, but I hear the clicking you describe in the dash.  It's like it can't decide to lower the seat or not.  I just happen to notice it last week.  After that amount of time passes, the seat does not move like normal if I get out.  All goes back to normal when I restart the truck and get out later.  I noticed all this while the wife was shopping and deciding to stay in the vehicle while she was chasing bargains   You know how the radio will stay on for a time if you don't open the door?  That's the amount of time that expires before I hear the clicking.  There may be other things happening, but I haven't worried too much about it.   

[A321Driver]

yeah about that amount of time, sat there and listed again, definitely sounds like a bunch of relays opening or closing and sounds like doors opening or closing in the heating/ac system.  I haven't noticed the seat position but I have not set up the exit position as I already sit back being 6'3".

[Anacortes Army Guy]

This is normal, and like already mentioned it sounds like relays, ventilation components actuating.  Mine does it at just under sixty seconds after shut off.  I do not think it has anything to do with the seat as I have the base power seat without the fancy ejection seat option.

[ericarenee]

19 minutes ago, Anacortes Army Guy said:

This is normal, and like already mentioned it sounds like relays, ventilation components actuating.  Mine does it at just under sixty seconds after shut off.  I do not think it has anything to do with the seat as I have the base power seat without the fancy ejection seat option.

same as mine no power seat

[JimCost2014]

I have the base power seat without the fancy ejection seat option.

 

Seems like we all have one regret on things we should have got after the purchase

[lebag335]

I understand this to be a normal function.  It's the brake module self checking.

[Transient]

I think you all are wrong.  It's the hamsters getting off their wheels and taking a little time to rest, eat, and drink.  It takes a lot for them to be able to move or trucks and haul our rears around. 

[rbdjr]

Fuel pressure bleeding off exsesive, and turbo vanes actuating cleaning procedure automated.