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2004 Jeep Liberty battery not charging properly


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wonderboy2005
New User

Sep 6, 2010, 10:46 AM

Post #1 of 5 (9498 views)
2004 Jeep Liberty battery not charging properly Sign In

Hi guys, I could use some help. First off, the info about the car:

year: 2004
Make: Jeep
Model: Liberty (Renegade)
Engine: 3.7L V6

So here is the problem. A couple days ago, the vehicle started struggling while turning over. After a couple trips, it made a number of clicking noises prior to starting. Finally, it would only make the clicking noise and wouldn't start. When this happened, I assumed it was a battery issue and had someone jump me. When it was jumped, the vehicle started without issue. I drove it for ~20 miles after this to charge the battery, and for a day or so, it seemed to work fine again. However, today it started making the clicking noise.

I assumed there was something wrong with the battery or the charging system, but I'm not entirely sure what it is yet. To test it, I purchased a digital multimeter. Here is what I've discovered so far:

The battery, while not being charged, is putting out ~12.7 volts. Note that this is only prior to a good start; I haven't been able to test the battery immediately before it has failed to start the car.

The alternator is putting out ~14.4 volts while the car is running.

There is no significant resistance between the positive and negative terminals on the battery. The meter reads .1-.2 ohms when touching the leads on the meter to each other, as well as when I attach them to the battery terminals.

I've been able to get the battery to charge via the alternator by going a decent distance (~20 miles). Because of this, I am fairly sure the alternator is not the problem.

I don't have any electrical additions or anything plugged into the battery of the vehicle that could be draining the battery. I did have a cell phone charger attached to the cigarette lighter, but I removed it as a troubleshooting step after the first incident. The issue came back, so I assume that the cell phone charger is not the culprit.

As an additional note, the issue started happening immediately after I switched jobs. This is significant because my previous job required that I drive ~50 miles a day. I can walk to my new job, and thus only use the vehicle for short trips in town, which likely are not allowing the battery to recharge like my previous daily commute.

My guess at this point is that my battery needs to be replaced. However, I'd like to hit up those more knowledgeable than I to determine if this is the case and to determine if any additional troubleshooting should be done.

That being said, any suggestions?

Thanks in advance.

-Scot


Sidom
Veteran / Moderator
Sidom profile image

Sep 6, 2010, 11:52 AM

Post #2 of 5 (9484 views)
Re: 2004 Jeep Liberty battery not charging properly Sign In

1st let me start off with saying "good job" on the thorough inspection.

You've used some good methods and sound logic. You've pretty much narrowed it down to a battery problem. The next step would be to load test the battery and that should tell you for sure if it's capable of holding a full charge. If this is the OE battery for the vehicle, then the odds are very high it's bad.....

Normally I would just leave it at that but due to how in depth you went checking this out, I'll just offer a couple of variations you may or may not want to use.

Another way to check for excessive resistance in the circuit would be to do a voltage drop test on the circuit while under load (running or cranking). To test the cables you would probe the batt term with the pos probe and the cable end with the neg probe. while running, anything over .3 v would indicate a resistance problem. Reverse the probes to check the negative side and on the ground side you don't want to see any more than a .2v drop on a loaded circuit... While using an ohm meter will catch a resistance problem, the thing is you aren't testing a loaded circuit and some problems won't show up until the circuit is loaded....

Another test besides loading a battery would be to check the specific gravity with a hydrometer. A fully charged good battery will show an SP of around 1.265. For this test to be accurate the battery needs to be fully slow charged just for the fact the cells can discharge at a different rate & give false reading. On a fully charge battery you don't want to see more than a 50pt variation. If you do a individual cell probe you would be looking for around 2.2 volts per cell and no more of a .5v variation...

State of Charge Specific Gravity Voltage 100% 1.265 75% 1.225 50% 1.190 25% 1.155 Discharged 1.120

You have used some good methods in tracing this down and I just offered a couple of different ways of "getting there". If you have any questions about this, just google "voltage drop testing" or " battery specific gravity"

It looks like the charging system is working by charging at 14.4. You could load the system by turning everything on, especially the heated back glass if it's equipped with it....Fully load the most you would want to see would be a 1 v drop any more would indicate the alt may not be able to keep up with the demand....

As far as a parasitic draw. If you have an amp meter or clamp. Hook it up to one of the batt cables with everything off & you don't want to see any more that .50-.75 Ma draw on the system. A quick check method would be to hook a test light between the neg terminal and cable while it's disconnected and the light should stay out. If it comes on there may be a draw but this method isn't 100%

Good job..... I enjoy reading posts like this


(This post was edited by Sidom on Sep 6, 2010, 11:58 AM)


wonderboy2005
New User

Sep 6, 2010, 1:30 PM

Post #3 of 5 (9474 views)
Re: 2004 Jeep Liberty battery not charging properly Sign In

Thanks Sidom, I appreciate your help.

The battery does appear to be the original. It is a Daimler-Chrystler branded battery. I can't say for sure, as I have only owned the car for the past 9 months.

I loaded down the alternator by turning on AC, rear defroster, headlights, bottom fog lights, top fog lights, and the radio. The voltage changed from about 14.38 to 14.30. Nothing significant, so I think we've ruled out the alternator.

I hooked up my multimeter in series with the battery and cable to check the parasitic draw. My meter says its drawing ~25 µA without anything on or plugged in. This seems definitely acceptable, maybe even low. I doubt this is my problem either.

I also checked for resistance while running, as you suggested. The measured voltage was ~.3v, so I think we're good on that front too.

I think I'm going to spring for a new battery. Even if its not the issue, It won't hurt to have a new one.

Thanks again for your help.

-Scot


Sidom
Veteran / Moderator
Sidom profile image

Sep 6, 2010, 2:34 PM

Post #4 of 5 (9472 views)
Re: 2004 Jeep Liberty battery not charging properly Sign In

No problem..... Glad it was an easy fix.....


wonderboy2005
New User

Sep 6, 2010, 3:22 PM

Post #5 of 5 (9467 views)
Re: 2004 Jeep Liberty battery not charging properly Sign In

The battery seems to have been the problem. I had it replaced, and it starts like a champ. I'll keep an eye on it just in case, but I feel pretty confident that its working properly now.

-Scot






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