My 2005 Jeep Wrangler X is the first new car I had and I do most of the maintenance on it myself along with my father. The past few days it's been having trouble starting. When I go to jump it and then disconnect the cables, it dies again. My father, who has worked on his own vehicles for years, is thinking it's the alternator and not the battery. Has anyone had this problem? Any ideas? I had the Jeep now 2 yrs 3.5 months and it has roughly 39,500 miles on it.
Your dad is probably right. With the Jeep running you should be able to disconnect one of the battery cables from the battery and it should continue to run off the alternator. First make sure the cables are clean and tight and also make sure that the belt Tensioner has the belt tight and if none of that is the problem, then pull the alternator and the battery and take them to an auto parts store that can test them for you. With the age of the Jeep your battery is probably still ok, but if the alternator is bad, that means the Jeep and all the accessories have been running off the battery and have put a strain on the battery, so you might have to replace both the alternator and the battery. Good luck and let us know the outcome.
98 Sport 4.0 Automatic, with a Dana 44 up front and 4.56’s and a Ford 8.8 in the rear W/ Detroit Locker and 4.56's. 35X12.50X15 Goodyear MTR’s mounted on Mickey Thompson Side biters. Rubicon Express 5.5 inch Long Arm lift. Rock Crawler type bumpers front and rear. 9500lb winch, Poison Spider rocker guards. .
I learned in auto tech school that batteries (no matter how much you pay for em), are good for about two years. After that, the battery is living on borrowed time (the reason for pro-rated warranties).
Pulling the battery cable off the battery to check the alternator worked in the old days, but with modern computerized vehicles you need to have them both checked. Just like 04tjinsa recommended make sure that your battery terminals are clean and free from corrosion, and aren't loose.
Your local autozone should be able to test both.
I dunno, because deep-cycle optimas are made a little differently. But I replaced a handfull of red tops when I worked at the local Lube, oil, and filter place, so I guess they go out just like everything else.
So let see, have your dad connect your battery with jumper cables to his car (running) to charge it for 10-15 minutes (your jeep is off). Then disconnect the jumper cables and start your jeep. Have a light inside your jeep running too. It should start up right away. If its the alternator that is bad then in about few minutes of it running the lights should start getting dimmer and it should die out. You can turn on the headlights after few minutes of it running to speed up the process.
Thank you for all your suggestions. Before my father took the battery and alternator to an autoparts store, he messed arround with it in the driveway. After connecting and disconnecting the battery a few times and testing that and the alternator, one of the screws at the battery terminal came out. It wasn't lose, it seems we tightened it too much that it actually went through the terminal. He replaced the terminals for me and by the time I got home from work everything seemed to be working fine. To be safe though, I ordered a new battery cause I'm sure that got drained some over this past week. In case something like this ever comes up again, I will use all your help.
Sounds like it might be the alternator, but can't say for sure. Call some auto parts stores around your area and ask if they can bench test alternators. If one of them can, take out the alternator and take it in. Or it might be easier for you to take out the battery and have that tested.
most likely it is the batterey if it the cables are unhooked from the battery, like the positive wire.. to make sure you would have to test the alternator for voltage output with probes.. should put out about 13-14. something volts.. or whatever it says on the alternator. no more than 15 though.
IMO I was a mechanic for years, it sounds like the alternator. 99percent sure.