How do you check alternator for parasitic draw?

How do you check alternator for parasitic draw?

To do a quick alternator drain power check using your digital multimeter, go to the section Bad Alternator Diode Test below. Then, if your alternator passes the test, do a battery check using a hydrometer tool as described in the Car Battery Hydrometer Test section.

Can a bad alternator cause a battery drain?

Obviously, batteries sometimes fail on their own–but a bad alternator can actually cause the battery to drain because it’s failing to recharge it. If your battery goes dead, have the alternator checked when replacing the battery so it doesn’t happen again.

Can a bad alternator cause parasitic drain and still?

Just because your alternator is providing 14v to the OBD system doesn’t mean it has enough amperage to charge the battery correctly. Based on what you’ve said, it sounds like either bad alternator or some parasitic drain, my money is on alternator. seems to be the case with my dakota..had the alt.tested and shure enough it has a bad diode.

Can a bad alternator kill a new battery?

The same situation could happen again with a new battery, if you miss signs of a failing alternator. Many people, even professionals, are quick to assume the battery is bad, but this can be a costly assumption if your failing alternator kills your newly replaced battery, too.

What are the symptoms of a bad alternator?

BAD ALTERNATOR SYMPTOMS: 1 Dim lights. The failing alternator symptom most drivers recognize is dim or flickering lights. 2 Service engine light. Another obvious sign is the one your vehicle tries to tell you. 3 Odd noises. 4 Electrical issues. 5 Engine stalling. 6 Dead battery.

What should I do if my alternator does not pass the battery test?

Then, if your alternator passes the test, do a battery check using a hydrometer tool as described in the Car Battery Hydrometer Test section. Reading above range: A higher amperage reading means you have a problem in one or more of the electrical circuits.