Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "What franchise can't fix in two months Louis solves in 20 minutes. Franchise = :'(" video.

Probably an engineer from the same school that put BMW 3 series Comfort module (the part that controls starting the engine) in the same data line with keyless door handle electronics. When the keyless handle electronics fail, the engine cannot be started and the car diagnostics stop answering questions. For another educational video, see https://youtu.be/B7gggowzPSE
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@drumguy1384 It wouldn't be that bad IF manufacturers had publicly available documentation about the expected voltages and waveforms on all lines. With info like that, it would be easy to find out the problematic circuit. Even better would be a system that could monitor such errors automatically and report the results using dedicated data and power lines. However, modern engineering cannot create such things, it seems.
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