I am not 100% sure if my 2016 V60 has a battery intelligent sensor but I'm guessing that little square computer board / chip attached to the negative cable is part of it.

I had a 2003 S60 and a 2011 V50 and changed batteries on those cars without any problems but maybe they didn't have the battery sensor.

1. Does my 2016 V60 have such a system
2. Is using a memory minder good protocol to use when changing batteries

Each year more and more and more stuff is added to cars. I may just start finding older models that are in good shape. Our 2011 Honda CRV has 120,000 miles on it and not one problem.

My 2016 V60 has a file of service appointments that may rival my older Jaguars.

You can replace the battery just like in the old days, BUT, you will need to zero out the counter in the CEM. If you have access to VIDA, great. If not, you will need to leave it at a mechanic overnight.

There are 2 different battery sizes!

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Keeping it running is better than buying new

Dealer got back to me about the battery drain. After three days they say that Volvo USA said to replace the battery and the siren control module. They are assuming the siren module was draining the battery.

I've seen youtubes that show disconnecting the connector at the ground cable that is part of the chip will erase the low battery light. That may be true but I would believe it doesn't re-set the battery counter. Right?

I hate 'assumptions'. Easy enough to determine if the siren control is the problem - disconnect fuse and check the battery voltage.

Correct, VIDA must be used to reset the battery counter.

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Keeping it running is better than buying new

My dealer charges something like $100 or more to hook up to VIDA. Kind of makes for expensive batteries.

It took the dealer almost 4 days to come up with something. You would think they are building a rocket to the moon instead of finding a battery drain.

Oh well - if it was the module that kept running the battery down it better be covered under the CPO warranty. That battery has reached a low charge too many times to be healthy.