A couple days ago my car wouldn't start when I tried starting it on the way back from school. (the tach lights were BARELY visible at all when the key is turned to ON). So I got it jump started and drove it home and it wouldn't turn it on again. So I did some research and found that the culprit may be diodes that went bad in the alternator. My dad insisted that it was the battery that needed to be changed so he changed out the battery. He took it to a nearby shop and they told him that the culprit was in fact the battery and not the alternator. I hope he's right because I rather have the battery go out on me than the alternator lol. I doubt it because my tach would flicker occasionally before it went out on me and I've heard that is a sympton of the alternator failing. What can I do to make sure that the problem is not my alternator? Thankss in advance.

 

I believe you can check by removing the negative terminal off the battery after you've started the car and if it the car shuts off then it's usually a sign of a bad alternator...plus you'll know if it's the alternator now if the car begins having start up issues again since your dad replaced the battery. hope that helps

 

the only way to say you have bad diodes is you get flickering dash lights at idle. sounds like its something else

 

@toniotran, i'll try that out.

@MasterForce, I used to get the occassional flickering dash lights before it went out on me but ever since I switched out the battery, it hasn't flickered so that is why i'm stumped.

 

it sounds like you have a bad battery.

 

[QUOTE=[APtwo],Aug 31 2010, 11:03 AM] @toniotran,

 

I've had the exact same problem in my Ap1 that you've mentioned, OP! Of course, I also started with the battery, but the car died on me on the interstate, so I was sure it wasn't the battery lol may I suggest changing out both- the alternator as well as the battery? That did the trick for me...

 

im having this exact same freaking problem right now with my AP1. i heard its the diodes in the alternator. its a 1 year old battery, original alternator with 62k miles.

i cant even jump start this car...

 

THEY CAN check your alternator at your nearest auto zone.

 

Haven't gotten a chance to check if the car stays on if I remove the negative from the battery but can anyone confirm if it means the alternator is bad if the engine shuts off?

I'll probably make sure at an auto-zone though, do they charge for a check up?