[xg15]

Well, the whole point of car inspections is that "your responsibility" is not enough. It's possible that you as the owner of a modded vehicle are perfectly fine with the risk of an accident, but the other potential participants of such an accident might not.

I think the question has a point: Modified ECUs are different from modified brakes, because the modifications could likely not be found in an inspection - in fact, according to the exemption, it would be illegal for inspectors to check the ECU. So I wonder how that problem is handled.

[alkonaut]

The simple solution for safety I think is to just include the software checksum/signature in the approval documents for a car model.

At an interval check, the inspector does the usual sampling tests (brake effect, emissions, looks for rusty brake lines etc), and then validates that all critical computers (ECU's and other systems such as computers related to brakes etc) run software that match the signature of the manufacturer, and that it is the latest version of the sowftare. After a recall such as the VW case, the inspector could fail cars that haven't upgraded to the latest version (which would be required since the original one is known to be cheating on emissions).

This is a bit harsh compared to other modifications: an owner can put on a set of extra lights or cool wheels without necessarily failing an inspection, whereas even changing a single bit of the software would immediately fail it in this case.

I can't see any way around this though, apart from separating programs into critical (brakes, ECU) /non-critical (Media, nav,...) software, where only the critical software would be checked.

[ams6110]

It some states it is your responsibility. Inspections (for emissions or safety) are not required everywhere. This is part of the reason that generally, the owner of the car is liable for damage it causes, whatever the reason or whoever is driving.