[anfilt]

Apple will won't honor their warranty if you jailbreak your phone which is kinda similar to modding the firmware on ECU. Do you think car companies are going to be any different if they can get away with it.

In the case of Apple it's pretty hard to justify the court costs for a 1000 dollar device. So Apple rarely has to prove that the Jail break was the cause of the failure. They technically can't deny warranty claim if a modification was not the cause of the failure. However, Apple operates basically by default for almost all failures if Jail Broken you get no warranty which is technically not legal.