What happens when an alternator has a short circuit?
These short circuits may develop severe mechanical stresses on the armature coils and their end turns or large torques, which may damage the alternator or its prime mover.
What to do when alternator dies when power is applied?
You will need to check to make sure all of the wiring on your power side is not touching ground before going through the components. Disconnect the big main cable to the alternator and see if the short goes away. If it does, then use your meter to measure the ohms between the alternator post and the alternator case.
Why is my alternator draining my car battery?
Since the alternator isn’t generating vehicle electricity, the problem component pulls from the battery, slowly draining it overnight until your vehicle won’t start.
Why does the alternator keep blowing when power is applied?
When I check for continuity from the positive battery post terminal to the casing of the alternator or any area of the grounded engine block, I get continuity. So when I hook up the 12v. DC and try to install a 60/70 amp maxi-fuse of course it keeps blowing for I think I am creating a dead short.
What happens when the battery is disconnected from the alternator?
Firstly, with the battery disconnected you will have continuity between the positive cable to the ground of the body or engine if you have any components hooked up or have fuses in. You are getting a complete circuit through some of these components.
What does it mean if your alternator is shorted in both directions?
You should have continuity in one direction and if you switch leads you’ll have no continuity. This will tell you the diodes are good or shorted in the alternator. If you have continuity in both directions then the large post is grounded or the internal diodes are bad.
What causes battery drain in Advance Auto Parts?
While you’re under the hood (or at Advance Auto Parts), test the alternator. A failed diode in the alternator creates a closed circuit that drains your battery even when the engine is off.
You will need to check to make sure all of the wiring on your power side is not touching ground before going through the components. Disconnect the big main cable to the alternator and see if the short goes away. If it does, then use your meter to measure the ohms between the alternator post and the alternator case.