Jeep battery died

[bassman284]

Trying to figure this out. I parked my 2008 Jeep Grand Cherokee in the garage about noon on Saturday. Went out about noon on Sunday it was completely dead. Dash lights didn't even come on. Checked it with the multimeter and it read 4 volts. I checked everything to make sure nothing had been left on and nothing was.

I put the charger on it (10 amp automatic), hoping for the best, and it seemed to be charging. I left it on overnight and by the next morning it was showing fully charged. Volt meter showed almost 12.9 volts. About 2 hours later it was still showing 12.8 so I fired it up and went for a ride. Everything appeared to be working OK except the radio which was completely dead. The radio is AM, FM, CD, Sirius and backup camera equipped.

I checked it this morning and it showed 12.7 V so the battery appears to be holding a charge. (AC Delco 800 CCA a little less than a year old.) So it appears the big current draw is no longer drawing.

So here's what I'm trying to find out. What could draw that battery that low in 24 hours? As I said nothing obvious was turned on. With the radio now being dead, I'm suspicious that it might be the cause. Does anybody think that's possible? My plan is to watch it for a couple of days and then maybe take it some place to see if they can figure it out.

Thanks.

 

[Scott Danforth]

take the battery and have it tested. you should be closer to 13 volts for a charged and healthy battery. my guess is your battery needs to be replaced.

 

[GA_Boater]

Is the radio a theft protected radio? With the battery dropping to 4 volts, you may need to enter the code to enable it again.

It's a Chrysler product - was your door ajar? That was a light on the dash a few years ago, during the K-car era and they caught a lot for flak over the word. It's not a jar, it's a door. :smile:

Anyway, a partially open door may have left the interior lights on and it wasn't noticed in the daylight on Saturday. A thought.

 

[bigdee]

Like scott said, a bad battery. Not uncommon for a battery even if it is a year old. If your charger has a de-sulfate mode try that to see if you can bring voltage up to +13. The Delco in my Jeep crapped out at 2 years.

 

[Scott Danforth]

here in FL, batteries die all the time under their warranty period. I keep a photo-copy of the original receipt taped to the side of the battery to aid in replacement.

 

[MTboatguy]

One other thing to check is the separate power amplifier interface, if they go kaput, they can drain the battery down to nothing, I believe that year had an external company stereo system in it and Chrysler has had many famous problems with those systems, my Jeep Grand Cherokee had a Bose system in it and it caused all kinds of problems until I replaced it.

 

[Sprig]

Something drained your battery. I don’t know what but I assume it’s related to the radio/stereo system. I doubt the problem is a bad battery since the next day after charging the voltage showed 12.7 which is 100% charge. Just to be sure take your battery and have it load tested. If it’s holding a charge and the load test is normal then it’s not your battery .
As long as you are at it check your alternator. Doubt the alt. has anything to do with your problem but check it anyway. With the vehicle running check your voltage at the battery terminals. You should get around 14 or more volts if the alt. is good. I think you are going to have to track down the problem that drained your battery. You may need a pro.

 

[crazy charlie]

QUOTE "The radio is AM, FM, CD, Sirius and backup camera equipped" END QUOTE AFTERMARKET for sure ,the way aftermarket is wired is usually the cause of electrical issues.How OLD is the battery?? This is the million dollar question so tell us. Vehicles now have current sensors so when the battery is showing weak to the vehicle computer,the current sensor cuts off the power to the ignition to keep the computer live but it acts like a totally dead battery.You are in for a surprise when u replace it.Thats an expensive one.That vehicle calls for a very big battery even for a V6 engine.Charlie

 

[matt167]

alternator will drain the battery if the diode pack is going out. Allows current to go the wrong way to ground. If this is the case, your alternator will be generating A/C voltage that you can pick up with a DVOM ( 1/2 volt A/C is normal, anything over 1v is suspect ). The stereo could also be going into protection mode if it senses A/C since aftermarkets actually have a protection mode usually

 

[bassman284]

Yeah matt, alternator diode was actually the first thing I was thinking of. Now I'm not so sure but when I go to the shop for diagnostics I'll mention it. This is NOT an aftermarket radio. It's original equipment.

 

[bigdee]

QUOTE You are in for a surprise when u replace it.Thats an expensive one.That vehicle calls for a very big battery even for a V6 engine.Charlie

Yes it is I replaced mine with a size H6 vs H7 and saved $100. It has same H x W but length is 1" shorter and fits battery tray just fine.

 

[Tim Frank]

.How OLD is the battery?? This is the million dollar question so tell us.

^^^^^

 

[bassman284]

The battery is less than a year old. Installed May 25, 2018.

 

[bigdee]

The battery is less than a year old. Installed May 25, 2018.

Your warranty should cover the first year at 100% replacement....what are waiting on!

 

[bassman284]

Your warranty should cover the first year at 100% replacement....what are waiting on!

The battery is fine now.

 

[GA_Boater]

So it's been holding a charge for a week now.

I still go with the interior lights were on overnight. That happens too often.

Is the radio working now?

 

[bigdee]

I have a 2008 Jeep GC and the interior lights and radio will not stay on for very long if vehicle is left un-attended. I would be very skeptical of that battery and since it is under warranty I would replace it. I have had batteries act in a similar way and intermittently fail. Sometimes it is a bad internal connection between cells. For piece of mind, DEMAND a new battery!

 

[bassman284]

:Yeah, the interior lights go out after a few minutes. Radio still dead. Going to call mu mechanic in the next day or so.

 

[ezbtr]

On my 99 Yukon, it was the passenger side vanity mirror light!!

 

[Bob_VT]

You might have a vampire of some sort draining the battery........ normally if a battery drains to below 6 volts it is officially dead and I personally would not trust it to become fully useful again.

Now I have seen the electric seat adjusters stick and drain a battery is very short order......