What causes alternator to keep failing?
Bad diodes are a common cause of alternator failure. If only one or two diodes have failed, the alternator may still produce enough current to meet the vehicle’s electrical needs, but it may not be enough to keep up with higher loads or keep the battery fully charged. This could cause the battery to run down over time.
Can a mechanic test an alternator?
Most service stations can test an alternator, but they will charge you for the labor. Many auto parts stores will test alternators, starters and batteries for free, though you will have to remove the alternator to have it tested at an auto parts store.
Can a bad alternator cause a battery to fail?
Yes, you still have a problem when you have a new battery and a bad alternator because a bad alternator can destroy a working battery when it charges it using too much voltage. Higher than recommended voltages lead to premature cell failure within the battery.
Why does the battery light come on after the alternator is replaced?
This would make the Battery Light come on. It is also possible that there is a problem with the fusible link or the alternator fuse for the charging system.
What should I do if my alternator keeps dying?
The alternator is essentially a generator and it keeps your battery charged while supplying additional electrical power for the other systems in the vehicle. If you have a new alternator and your battery keeps dying on you, then there’s definitely a problem that you’re going to need to look into.
How can I tell if I have an alternator problem?
To differentiate an alternator problem from the battery, you will need to use a voltmeter to check for voltage. First, turn off the engine and check the battery voltage. A fully charged battery should have a reading of 12.65 volts. Next, turn on the engine and recheck the voltage. You should have a reading of 13.5 to 14.5 volts.