Alternator? Battery?

[johnnyboy_10138]

So I took the dodge to Autozone for them to test the battery and alternator. My truck dies after about a week of sitting, which is every week because I cant leave the base. The Autozone guy, who really didnt know how to work the machine, said that the Alternator wasnt putting out enough amps, but he only had me rev it to 1000RPM when testing. After the grid heater turns off I have 14 volts on the dash gauge all the time, even when I have my subwoofers turned on and up. So this really seems like a charging or battery issue to me. I have 118k on the original batteries. The cables and connections look good, some acid build up around the battery terminals, that is about it. I dont have a place i can work on the truck and leave it disassembled while i pull the alternator, so i am hoping it is just the batteries. What do yall think?

Oh, and I have liberty tomorrow, so I am hoping to get this done then.

 

[Skydiver]

Thanks for serving our Country.
More than likely batteries. The truck volt meter will read higher if the corrosion build (acid)up is restricting electrical flow. How many watts is your audio system? Do you run the audio without the engine running? I would clean all 4 terminals first.
Can you get your hands on a volt meter?

 

[RobertHiltz]

Andres is right, likely the batteries. Did Autozone do a load test on each battery? Are you setting any low voltage codes? Do a load test and if one battery is bad replace them both.

 

[johnnyboy_10138]

The audio system is 500 watts, But i never run it even close to that loud. I just went with good quality . I only run the system when the truck is running. I can get a voltmeter. What should i test for?



Everything turns off. Could the Bully Dog Outlook monitor be drawing energy when the truck is off?



I am throwing no codes. I dont believe Autozone load tested the batteries. Hopefully I can get the truck jumped today and figure this out.

 

[jelag]

If you turn every thing on in your truck and the voltmeter still reads close to 14 volts there is a very small chance its the alternator...

One of the ways batteries can go bad is they build up too much internal resistance and won't take a charge from the alternator... but will charge from a battery charger... .

Here's why... the alternator is limited to just above 14 volts under the right conditions so that the batteries are not over charged... a battery charger will easily run the voltage up to 15. 5 to 16 volts to overcome the internal resistance of the battery and charge it...

So if you find the batteries dead, can charge them with a charger and the truck won't keep them charged its a battery problem... . Since the internal resistance of bad batteries is high, you charge them with a charger and each time you start the truck you run them down... . the alternator won't charge them enough over time to keep the batteries topped off...

Hope this helps understanding the problem. .

 

[TCDiesel]

If the truck is going to sit. The draw from the airbags and system will kill the Batteries in short order even if the IOD fuses are PULL. the system is designed to Keep a Charge. low Batteries (Continually) will cause quick failure of the charging system. Just remove the Negative connections on the batteries.

 

[johnnyboy_10138]

I can get a good multimeter from the electrical engineering department to test for the parasitic draw. How many amps should the clock and radio pull?

The truck sit from Sunday to Thursday. I make sure to start it every Thursday to charge the batteries and stuff. Is that long enough to need to unplug the batteries.

Before I had a remote kill switch for my jeeps battery, I could leave it for like 4 months and it would turn over no problem, it wouldnt start up, but that is the 25 year old carb on it.

 

[johnnyboy_10138]

Thanks for all the replies. I will check it out this afternoon and let you know what I find.

 

[johnnyboy_10138]

So I am pretty sure I figured it out. I have a remote jumper cable hook up. It is like a plug under my bumper. Turns out snow got under the cap and well snow=water, which was shorting out my battery. Atleast that is what i am thinking. Took about a half hour to get the truck to finally crank up, I went ahead and bought new batteries. Had a friend that wanted some cheap for his boat, so he is going to give me the core deposit if they work. Truck starts up better than it has in a long while.

But something weird happened when I finally got it started. Got about 8 codes thrown at me. The truck had absolutely no power. When in park and i punched the skinny it would take a little while to respond and then shoot up, and kind of gargle and die back to idle. When in gear, it wouldnt get any power. One of the codes was an ECM COMM error. I uninstalled the bully dog, and reset all the codes, and all is good now.

Found out i have a bad terminal connector on the driver side battery, replacing that tomorrow.

Thanks for all the help guys.

 

[rbattelle]

The truck sit from Sunday to Thursday. I make sure to start it every Thursday to charge the batteries and stuff. Is that long enough to need to unplug the batteries.

This shouldn't be a problem. I regularly leave my truck for a couple weeks and it holds a charge no problem.



Ryan