Walking to my car in the morning 2 days ago, press the unlock button on my key fob...and nothing. Again, nothing. Okay, figured key fob battery is dead, unlock it manually, and no lights, no accessories, nothing. Turn the key, absolutely nothing, no crank no noise. Got my work van and jump started it, started up just fine. Drive to work, about 3 hours later I go to check on it....and same thing. Tried to jump it again, this time it runs, and turns off within 1 or maybe 2 seconds. I had work to do and didn't have time to diagnose, so i let it be. That night, about say 8 hours later, I try to jump start it, starts just fine, drove it for a while, and parked it. All is good, in the morning, I go check on it, about 10 hours later and....its fine. Everything works, starts right up. Today, I go in the morning, press lock/un lock I can hear the horn slowly fade and interior lights are a lot dimmer.

I took the battery to a local advance auto, he said it's shot, I figured it is, but ask him to see if he can charge it, he charged it and it held the charge, so seems as if it's okay?

I figured I should also change the terminals, so I swapped the negative terminal, and before I can get to the positive, it started down pouring rain. Going to be raining for the rest of today and all of tomorrow, so I won't be able to work on it.

With the given information, anyone have any idea what it could be? Alternator, starter, battery, terminals? I'm all ears,

thanks in advance

 

Your local advanced auto should be able to check/test your alternator. Seems like your having power issues vehicle wide. I would start there. It's free, so you have nothing to lose. But definitely finish the new terminals first. My Cherokee has a loose positive terminal that I can't tighten very well to the battery post anymore. Sometimes, depending how it's sitting on the post, everything in the XJ will dead until I jiggle positive cable a bit. On my list to fix.

 

Hopefully I can make it there

 

 

check batt volts when started. appx 14+.
get a cheap volt meter at harbor freight,or?

 

I replaced the ground terminal but couldn't get around to the positive because of the rain. Hopefully that's the fix.

 

I will as soon as weather clears up and I can actually get to working on it.

 

If your battery fails the LOAD TEST, replace it right now. Failure to do so will result in the chasing of your tail and continued symptoms.

And yes, you should also verify your charging system is working properly. About 14.4 give or take a bit at idle is what you should read with a meter on DC volts on your battery.

And you are on the right track with replacing any hardware (wiring/terminals) for your battery. The importance of fresh connections cannot be overstated.

Good luck!

 

After you've addressed the wiring, terminals, alternator and battery and the problem persists, remove the IOD fuse from the PDC when you let it set to see if the battery goes dead again. If not there's an ignition off draw on the battery somewhere.



.

 

Okay all, thank you all for the replies.

2 days after changing the terminals, and all is fine. I took her to advance and had the charging system checked, and all is well.

However, when I first started it after changing the terminals, the oil pressure shot up to 80. It was running fine however. I turned it off, and back on, and at idle its sitting at 40, which was usually just under 20.

When i put any load on the engine as I accelerate, it goes up to around 50 (40 before). I'm not sure if this problem is related somehow? I am thinking its the oil pressure sending unit, but related?

thanks