I checked using a multimeter. Alternator is only showing battery voltage. I also did the negative battery cable trick. If you pull the negative and the car shuts off it’s the alternator. Also I don’t have anything going to the voltmeter in the dash.
No. Do not ever do this. This is an old wives tale and can cause damage to electronics, AND IT IS incorrect, EXAMPLE:
A: "Let's say" the alternator is perfectly fine, but the engine is idling a bit slow, and the alternator is simply turning too slow to provide enough output. You pull the battery cable and the engine quits ---you FALSELY conclude the alternator is not charging.
B: "Let's say" the alternator has a couple of bad diodes and so is operating at greatly reduced output. Maybe less than half it's rated current. You yank off the cable, the engine stays running, and you FALSELY conclude that the alternator is fine.
By the way for this fake false test, it does not matter if you remove the hot or ground battery cable.
