Interesting question.

Biggest risk when starting a 6 volt vehicle with a 12 volt vehicle is possibly burning out the gas gauge. A running vehicle may actually be at 15 volts.

I checked my NocoBoost with a voltmeter. It output is exactly 12 volts.

So, it's probably safer to start a 6 volt vehicle with the booster than with a running vehicle.


Gord 🇨🇦
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1954 1/2 ton 235 4 speed