another not charging thread
Doesn't this mean it was taking power from the battery? (I won't do it again 67Dart273)
I may have misunderstood your connections. What I was getting at is the old "wives tale test" It goes like this:
You start the car and run it and while running, you pull one cable off the battery. The "supposed" answers are that if the engine stops, the alternator is bad
WHY this is not only a bad idea, but WHY it does not prove much
First, with more and more electronics in cars, a voltage spike caused by a WORKING alternator can damage electronics
Second, the "test" does not prove anything, why:
1..."Let's say" the car happens to be running quite slow, and the battery somewhat down, and you happen to have "maybe" left something like the heater blower on low. "It might just be" that when you pull the cable off, a WORKING alternator might not be able to put out enough at low RPM to keep things going, and you might wrongly conclude the thing is bad
2...The OPPOSITE worng conclusion can come into play: Let's say you have no loads powered in the car, so minimal draw. Let's say you have the engine idling fairly fast RPM. Let's say the alternator actually has a BIG problem, like 4 of the 6 diodes are blown open. So the alternator is not putting out "much." You pull the cable, and it keeps right on running!!! So you "think" the alternator is good!!! When, in fact, it is barely able to provide basic ignition power, (and in addition delivers an incredibly dirty output wave)
