Buy an OBDeleven or VCDS if you own a VW and are doing any work on it yourself.
You can also adjust features (roll up windows with remote, etc). Run diagnostics in real time while driving, test every switch/sensor on the car.
Also, it is needed if you do a brake job on the rear brakes to open/close the parking brake so you can put the pads in.
I don't believe you need to recode the battery if you replace with the exact same battery but you need to change it if you don't put in the OEM one [1]
Yeah we don't have the source code. But with long coding adaptations in the system you can do a large portion of what you need to do (engine/trans swaps). If going deeper is needed there are companies who reflash/recode ECUs but that is about as deep as you can go without doing independent module hacking.
LiFePO4 batteries that you'll find in some vehicles (more often than not for running accessory loads, not starting the engine - though some models are intended for dual purpose use) usually have a decent degree of intelligence baked into an on-board BMS system.
Typical car batteries are not yet so 'smart'. The post-battery-swap 'coding' that many euro vehicles need is to instruct the car-side BMS about the battery's characteristics so that it can tune things like its start-stop routine, alternator behavior, etc. to optimize battery life and resilience.
You can also adjust features (roll up windows with remote, etc). Run diagnostics in real time while driving, test every switch/sensor on the car. Also, it is needed if you do a brake job on the rear brakes to open/close the parking brake so you can put the pads in.
I don't believe you need to recode the battery if you replace with the exact same battery but you need to change it if you don't put in the OEM one [1]
Yeah we don't have the source code. But with long coding adaptations in the system you can do a large portion of what you need to do (engine/trans swaps). If going deeper is needed there are companies who reflash/recode ECUs but that is about as deep as you can go without doing independent module hacking.
[1] https://youtu.be/48w9Cg4ObEk