Frequently a bad battery can kill an alternator if you use it too long. It depends on the vehicle. For some reason 3 GM cars that we had had the same problem. A bad battery killed the alternator. It is also possible you are getting a cheaply rebuilt alternator.
Either case, they can easily go out in pairs.
***EDIT*** No,, it cannot be a bad sensor if they are testing it at the place. If their equipment says it is bad, it is bad. Just don't let it kill your new battery. Also locate your receipts and warranty information. ALSO LIKE Rick29148 said, make sure it is not just corroded or loose battery terminals. Otherwise rest all applies. Thanks rick29148.
the alternator needs to be tested, most of them are internally regulated any more. there is not an external sensor. 2500 rpm is a bit high to get it to work. the out put should not be as high at idle but it shoudl still charge at that point.
Hi in all this there is no mention of taking it to the cars maker dealership which makes me think there in lies a clue as to why yo have had all these issues.
so makes are having issues with anything other than genuine parts. BMW and Mercedes being two which suffer as having non genuine parts fitted.
not enough info dude. what kind of car? if the voltage regulator is external then that's probably your issue.
year make model engine would be huge.
So 2 months ago my altinator went bad
Replaced it at oreillys
2 weeks later went bad again got it replaced
1 and a half months passed and today my battery light and break light came on
So I took it to autozone to get my battery and altinator tested
Battery new btw
Guy told me battery good to turn on the car and see if it's the alrinator
Told me step on the gas
After hitting 2500 rpm's the lights came off
And once i let it drop below 2500 rpm's they came back on
He sayed it's the altinator but I need a i sight look
Could it be a sensor or what?
