[T77911S]

i have been an electronics tech for the FAA since 1990. before i did some electrical work cars for a shop. i/we used a test light for the majority of the electrical work. the MM was mainly used for charging issues or to maybe to check a batt, but then we had a batt tester that could put a load on it to test it.

a MM can be misleading. i have been part of several posts here were guys were measuring 12v with their MM but could not figure out why the circuit still did not work. ( like a break light, or turn light).
a MM does not need much if any current to measure 12v. there were bad connections that prevented enough current from turning on a brake light or operating what ever it was they were working, but the MM read 12v.
putting a test light on that circuit would have shown that there was not enough current in the circuit because the TL needs more current than the MM does. look at it like this. if the circuit won light the TL, it wont light a brake light or turn light.

$100 for a MM
$10 for TL