Is this a bad alternator?

[jen.pagan]

I drive a '97 Jimmy and (like an idiot) left my lights on for almost 10 hours at school. When I came back to my car at the end of the day and tried to start it, nothing happened. No lights, no sounds, no nothing. I attempted to have it jumped 3 seperate times, and each time it was connected the lights would turn on and the power would come back, but it wouldn't turn over and start. It sounded like it wanted to but it just wouldn't turn over. I've had problems with the battery before but haven't had my wiring looked at. What makes me suspect the alternator is that when I pull up to stop lights, the car seems to shutter every once and awhile, almost like it's going to shut off.


Can anyone possibly diagnose the problem?

[MT-2500]

Originally Posted by jen.pagan

I drive a '97 Jimmy and (like an idiot) left my lights on for almost 10 hours at school. When I came back to my car at the end of the day and tried to start it, nothing happened. No lights, no sounds, no nothing. I attempted to have it jumped 3 seperate times, and each time it was connected the lights would turn on and the power would come back, but it wouldn't turn over and start. It sounded like it wanted to but it just wouldn't turn over. I've had problems with the battery before but haven't had my wiring looked at. What makes me suspect the alternator is that when I pull up to stop lights, the car seems to shutter every once and awhile, almost like it's going to shut off.


Can anyone possibly diagnose the problem?

Can anyone possibly diagnose the problem??????
No way we can test it.
Not over the net.

From what you have told us it sounds like a bad or weak battery or battery cabel connections.

If it will not turn over with a jumper.
Check cabel end connections and clean if needed.
If no help there
Remove battery and have it charged and tested.
A good battery has to be able to take a load test and come up to 13.2 volts.
If it charges up good and passes load and voltage test.
Install it back in and make sure cabel connections are good and clean.

If it does not pass test time for a new battery.

Also when jump starting a dead battery let the jumper car run a while to get some charge into your old battery before trying to start the one you are jumping.
When installing jumper cabels do not cross neg and positive and make sur ends of jumper cables are making a good connections.
Also have a good set of jumpers.
Theb light cheap ones do more harm than good.

Let us know how it goes.

[4x4 blazerguy]

MT2500 gave you some good advise. The only thing I want to add is that my experience with these newer vehicles & batteries is that once they go real dead they seem to short out inside & won't start the vehicle but will run lights etc when jumped. I have had this happen twice once on my 97 Blazer 4x4 & once on my 98 Jeep GC 5.9 Limited.