Sorry John I dont follow. Are you saying there should be continuity between the battery stud and ground?
Continuity question
- Thread starter Baker7888
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Yes. It is just like measuring a diode ... the current can flow in one direction but not the other.
Is your continuity tester a self contained unit with a battery inside? Then you can do the test on your own alternator. First make sure there is nothing connected to the output stud. Then connect your continuity tester first one way then the other. It should show open circuit and then continuity.
Is your continuity tester a self contained unit with a battery inside? Then you can do the test on your own alternator. First make sure there is nothing connected to the output stud. Then connect your continuity tester first one way then the other. It should show open circuit and then continuity.
It is. I did not think to try the other way.
However, I have continuity at positive and negative battery leads. (Battery not installed) I think due to faulty alternator. Is this normal? I could not replicate these results on my daily driver (battery uninstalled for test)
A continuity tester is meant for individual wires and for cable pairs. It is not the best tool for devices or circuits. Put the tester down and decide what it is you are actually trying to test.
On any vehicle the positive cable branches out to alternator, fuse box, and other hot points. Some of them are on at all times, or on while the door is open. If you have to, do the 2-way test on your alternator with nothing connected to the output stud. It is not a true test.
On any vehicle the positive cable branches out to alternator, fuse box, and other hot points. Some of them are on at all times, or on while the door is open. If you have to, do the 2-way test on your alternator with nothing connected to the output stud. It is not a true test.
Ok i will try that tonight when I get home.
What I am saying though is if i were to attempt to install a battery my belief is I would get instant arcing at the battery.
John, good call. I disconnected everything from the alternator and there is no continuity between the battery stud and the body of the alternator. Then I realized my key was in the forward position. When I have the key in the forward position I do have continuity between positive and negative leads but with key off there is no continuity. Is this normal??
Yes ... now you have x-ray eyes.
You can see what those little electrons are doing. There are 2 concepts that will help understand why. Try these links:
What is Ohm’s Law?
Ohm’s Law is a formula used to calculate the relationship between voltage, current and resistance in an electrical circuit.
www.fluke.com
Series and parallel Circuits - Well Explained
Current flow and voltage division in series and parallel circuits. Serial circuit and parallel circuit and current flow in it.
www.electricalclassroom.com
Thanks for the links. It hadn’t occurred to me key on/off. I replicated the test on my truck and did get continuity on the battery leads with key on. I now think the alternator in the Malibu is fine.Yes ... now you have x-ray eyes.
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You can see what those little electrons are doing. There are 2 concepts that will help understand why. Try these links:
What is Ohm’s Law?
Ohm’s Law is a formula used to calculate the relationship between voltage, current and resistance in an electrical circuit.
Series and parallel Circuits - Well Explained
Current flow and voltage division in series and parallel circuits. Serial circuit and parallel circuit and current flow in it.
Years ago there was a "starter rebuild" shop in town that was actually a "bookie joint." They had trucks driving around town to pick up "starters." At the shop they had long benches with starter parts lying around and several telephones at "workstations."
I got the story while with a shady neighbor who was dropping off a thank you bottle of whisky.
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