2020s CT6 2016 won't start after battery run dead

[TonyZappone #2624]

My 2016 CT6 platinum  is in the body shop for a fender bender.  The battery went dead (however it happened)  Car wont turn over now (after recharge)  Suggestions?

[Clewisiii]

My 2010 did that when I left the door open all day while cleaning. It gave me a security code and prevented me to start it after I charged the battery.

I disconnected the battery for a little while and reconnected and it reset.

[TonyZappone #2624]

Car had to be flatbedded to a GM dealership (on four dollies, on a flatbed), because everything was locked up.  Problem:  BCM (Body module had to be reprogrammed).  Body shop is finishing work

[V63]

These modern cars seem to deplete batteries in a short period of time if not driven daily. I'd suggest it's about 10 days. Best to disconnect battery if you can.

Also batteries 2 years or older become suspect.

[The Tassie Devil(le)]

With all the computers in cars these days, Batteries don't take long to discharge.

Even the simple clock drays current.

Bruce.

[TJ Hopland]

Disconnecting the battery may still require a tow to the dealer.  I don't know about this model specifically but its not uncommon with modern cars that the battery has to be programmed to the car as well as the possibility that other modules loose their memory and have to be re programmed too. 

The explanation why the battery has to be programmed is that the car is so smart it has to know about the battery so it can charge it the most efficient way possible and I think its supposed to start cutting of power draws if the battery starts to get low.  Seems like it could just give you a warning it needs to be calibrated rather than not work but not work seems to be the default.  The few people I know that are willing to work on newer cars say they change batteries with the engine running and most of the time as long as you don't blow up or short anything out they don't seem to notice and everything is fine.

Like with every piece of tech these days there are very slight nuggets of logic behind some of these issues but it mostly seems like 'they' are just making things that if they are repairable at all the only people that can repair the stuff is 'them'.  Its not just things that don't usually break it now usually includes wear items.  I don't know if Cadillac is one of them but there are cars where there are electronic sensors embedded in the brake pads.   

[The Tassie Devil(le)]

It could be that when a battery is changed, the computer "thinks" that someone is trying to steal the car, and shuts everything off so that doesn't happen.

Back in 2002, I had to replace the battery in the '89 Thunderbird I had just purchased for my tour of USA and Canada and when I connected the replacement battery, the doors immediately locked.

Trouble was that I had left the keys in the ignition, and the windows up, and you guessed it, the spares were with the keys in the ignition, and the owners manual in the Glove Box.

Luckily, the car had the outside number pad, and the previous owner remembered the unlocking code.

It definitely was a lesson to me to not get caught again.

Bruce.