I'm not too sure about this guy, he seems like a bit of a quack. A couple things in the video pop out at me:
1. He removed the positive cable first, never do that.
2. He's used a 1 Ohm, 10 Watt resistor, I wonder why he chose to use something of such high power rating.
The sound of his voice is enough to get me to stop listening about 10 seconds. I don't know how much he actually knows but he sounds enough like a lunatic for me!
If his goal is to discharge any residual voltage stored by capacitors in the ECM(or similar devices) power supplies, then yes this would work. But so would leaving the battery disconnected for whatever period of time it would take to have the capacitor lose its charge. As well, a 1 ohm resistor isn't much different than the resistance of a wire to be honest. In effect, he is shorting out the feed to these computerized devices draining any stored energy. Will it drain the residual voltage? Yes. Will it clear the codes, possibly. Depends if the memory is volatile or non volatile. No science to the 10 Watt rating. Just how much heat the resistor can dissipate. And my bet, its nearly zero in this case.
he has some decent videos - he's definately high strung... but maybe that's because he's trying to get as much info spoken while filming.
iirc most of his recent videos are more 'out there' than not.
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1970 Formula 400 Carousel Red on black (std) interior "no drivetrain option" car (same base drivetrain as GTO) 1:411 1970 Firebird Formulas originally sold in Canada