So i already have my appointment to test my alternator, but how do i know that is ok, what are the correct levels for the alternator, dont want stealership to lie and i dont know they are lying.


What are the correct numbers for alternator and battery tests ?


Thanks

 

If your car isn't dying, it's fine. And I think any voltage output higher than battery voltage is the range. Amp draw depends on running accessories.

 

i just got a new one...my car kept dying and it was whineing

and when my car was running, if i took off the negative battery terminal, the car would die.....it shouldnt do that so i knew what it was

 

Its not dying while running, but sometimes in the morning it seems it doesnt want to start, cranking is not alright feeling like it wont start.

 

Appointment why not just get a quick 30 second check from Autozone or something as a baseline test. Then make an appointment if something shows whack...

 

Well we dont have Autozone in Mexico City =( so i need to go with dealership to test alternatertor and battery.

 

A quick simple test would be to get or borrow a cheap volt/ohm meter and hook it up to the battery. With the car off it should read around 12.5 volts. while running it should be around 13.5 to 14 volts if the alternator is working right.

 

Taking the negative battery cable off while running is never a good idea. Maybe 'back in the day', but that is a BAD idea with all the electronic devices on modern cars.

 

good advice,the fastest way to kjill a alternator is to remove one of the cables with the engine running.the voltage spike can kill computers also.