Heres a scenario that I've been throwing around in my head for a while now....


Lets assume I go to the dealer parts dept and buy a new ecu. They set it up on my car to my vin etc. Then I take the "old" ecu and get it tuned. If something were to happen and my car would need warranty repair, couldn't I just swap the old tuned ecu with the new stock one and then take it to the dealer for repairs and they would have no idea of a tune on my vehicle?






...if anyone from JLR reads this, I'm asking for a friend...

 

First of all they would know that you had a second ecu since they sold it to you, then ecu doesn't just show you what is happening rn, there is a history of what have happened in the past, rmp history, oil change resets, etc so it's not just something that you can change and go back to the dealer