So this question relates to cars but applies to all electronic circuits really.
I was watching a car diagnostic video on youtube and in the video he demonstrates the difference between doing voltage reading while the circuit has a load vs no load. https://www.youtube.com/watch?v=0UO-e7bLsY4&t=397s (skip to 6:37)
Why does the multi meter show a steady 13V when connected to the circuit without an electric load, but as soon as there's a load the voltage drops to zero immediately? Shouldn't the multi meter show zero voltage regardless of whether there is a load connected or not since obviously there's corrosion in the wire.
Maybe I'm failing to understand how multi meter's actually measure voltage?