Battery does not stay charged!!!

75greenduster said

Excessive corrosion or a loose battery cable will keep your car from starting. If that doesn't fix your problem, don't be too sure that it isn't a bad battery. Did this problem exist before you had this battery? If it did then it probably isn't the battery. I had this same problem a few years ago with a brand new battery. Thinking that it couldn't possibly be the battery I replaced the battery cables, checked the alternator, and checked everywhere for a short. Turned out the battery I bought was no good.

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Well when I had the old battery on, it happened once, the car wouldnt start, i would just hear a "cluck!" in the starter, i removed the battery and sort of cleaned the ends and the car turned on.

Then one day i had a important doctor app. it happened again, nd i just didnt know what to do cuss i needed the car, so i bought a new battery nd it worked fine, not sure if i tightened the battery cables good enough or not but when i didnt use the car for a weekend or more the car wouldnt turn on again so what i did yesterday was again...

removed the battery wiggled it lol and cleaned nd tightened the cable ends, nd it worked.

How can i know if the alternator has a bad diode? should i just replace it?