krook wrote:multimeters help you determine exactly how much current is flowing through wires as well, whether they're 12v. or lower. not all wiring in a vehicle stays grounded or at 12 volts.
Yes, I already stated that.
krook wrote:a test light is good, but if you're not careful you could end up damaging something. a fellow installer at my workplace accidentally deployed the airbag with his test light.
HAHAHAHAHA! Why did he do that? The important part of that phrase, 'if you are not careful'. Most of the car is 12v, some are less sure, but mostly engine stuff. Headlights are 12v. And you can't really damage anything with a hot wire tester, except for piercing the wire you're testing would be the only way I can think of. Remember a light bulb is a resistor, it will show a current, and not blow anything, it will however complete whatever circuit you're testing, like the airbags. This is also what helped me discover the Independent Fog Lights mod. Why was he testing the airbags?