[superczar]

Apologies if this question has already been asked..
I did perform a search but most related questions are several years old:

On my F34 2017 (3GT Lci), I have made two changes over the last 1.5 years

1) Enhanced Bluetooth

• Changed VO code 6NH to 6NS
• Made a few minor updates (werte values) on the HU_NBT2 CAFD

2) Carplay

• Added FSC code for carplay 6CP
• Added VO code 6CP
• modified the HU_NBT CAFD for carplay

The car is under warranty till 2022

Q1 - Since I have added 2 new VOs, I suppose it is possible that some sort of a retrofit flag will pop up at the dealership next time the car goes for a service.
I presume it would be worthwhile to roll back the changes to get the car back to the original FA?


Q2: If I want to temporarily disable these changes before sending the car, do I just need to do the following:

• Update VO code to remove 6CP + change 6NS back to 6NH
  
• After VO coding, do I need to roll back changes on the CAFD too?
• I suppose not as I understand a VO code update will flip the coded ECU to default values on the CAFD anyway

Q3 - Once the car is back from service, DO i just need to update the VO codes again?
Or do i need to re-add the FSC codes also?

Q4 - Older electronics in the 90s / early 00s used to have finicky EEPROMs
Too much tinkering around with the firmware could quite often result in dead chips that would refuse to be re-programmed anymore
Now maybe I am being paranoid but I would rather take the risk of sending the car as-is to the dealership and take the relatively lower risk rather than flashing/re-flashing for a possibility vs the real risk of a dead ECU

It is probably worth adding that the 6NH to 6NS change was done over a year ago after which the car has already gone for 1 service with no red flags - although it is possible that this service was just an oil change and the dealership would have had no need to read the HU_NBT2 ECU