One way to find out if the alternator is going south is to get your car started first and while the car is running, disconnect the negative terminal to your car battery. If your car doesn't stall, then it is most likely your battery that is the problem. If the alternator was bad your engine would die because it not generating enough juice to keep it running.
Also if your battery is more than 5+ years old, it's probably close to it's life expectancy especially if you do a lot of short trips around town.
I hope this helps!
-Lee
So I just got an issue with my car today, heres what went on:
I went to work not problem (1 km drive), car started.
During my lunch break, tried to take it out but it would not start after multiple attempts. Would basically just click repeatedly but not start.
Later on my last break, I managed to start on the first try.
Then at the end of the day, would not start again like during the lunch break.
So my collegue boosts my car and it works (YAY) and I manage to get home (1km).
What does it mean? I figured that my battery is dead and I need a new one, since my car would have stalled on the way back home if it was an alternator issue? Am I correct in thinking this? I was thinking of getting a new battery and changing it myself, but I'd spare myself the expense if its the alternator.
(If it helps at all, my car is a Mazda Tribute 2002).

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