Battery issue?

[jillshubby]

Hello, I have a 2006 Dodge Ram 1500 5.7L Hemi. It is experiencing intermittent hard start. All of last week the truck started, and continues to start, but occasionally it will have trouble starting. Most of the time it starts normal, but it seems that if anything has had a chance to drain the battery even a little bit, then it will struggle starting the next time. The most recent example is yesterday when I ran into a coffee shop. I accidentally left the lights on, but it was only 5 minutes, yet when I got back in the truck and started it, it was very sluggish to turn over and barely had enough "juice" to start. I drove to another quick stop, did not leave the lights on this time, and this time it started completely normal. Another time I arrived somewhere early, sat in the truck with the radio on for 15 minutes, then the next time I got back in the truck a couple hours later, it was sluggish to start, but did start on the first try. So it seems that maybe the battery is draining very quickly if anything has a chance to pull power while the truck is not running...but if I simply drive it and nothing gets left on for even a few minutes, then it will start just fine every time.
Could this be that the battery is simply going bad?

The alternator is charging it well, and the battery reads over 14V with engine running, and about 12.8V after driving.

Thanks for your input!

 

[turkeybird56]

In all probability, battery going bad, maybe a bad cell. Have it load tested. All above symptoms of a battery going bad. You have a 3rd gen, but you should be seeing a charging rate 14.0 ish to 14.6 ish, depending upon battery draw. Sitting numbers OK, But if battery going bad, will read around your numbers and pooph out when U put a monster load on it. If U were to put meter on battery after truck shut down, lights off, all electronics off, U can sit there and watch that meter draw down. Internet guessnosis, but just my guess.

 

[jillshubby]

Thanks for your input! Here is a bit more info after some more testing.
I did a multimeter-style load test and set the meter to min/max while I started the engine. Battery voltage started at about 12.7V, then when starting the engine it reached a low of 9.2V, and maxed at 14.99 with the engine/alternator running. Based on it being lower than 9.5V at its low point during starting (I've heard that is the threshold to go by), I am guessing that the battery is bad. But at the same time I tested for parasitic drain and that seems to be an issue right now as well.

When the engine and all accessories off, and with either the neg or pos battery terminal disconnected (I did both ways separately), and a test light connected between the terminal connector and the post, the test light is lighting up bright, and with a very very slight pulsing to the light. You actually have to stare at the light very closely in a dark garage to notice the pulsing, so the pulsing is very subtle. I started pulling fuses to see what would shut off the test light, but the test light never turned off after pulling every single fuse. I did this at least 3 times through to make sure I wasn't missing any (once with the pos batt side and once with the neg batt side). This truck only has one fuse box to check, so I am at a loss as to where to go from here.

I also used a clamp amp meter on the battery positive cable and am getting about 2.5 Amps of draw with the engine and all accessories off. I got under the truck just to visually check any wiring that I could, and added some cable protector in two places that the existing protector was falling apart, and then I checked with the clamp meter again just to see if I would get the same readings, but now it was only reading 1 amp when clamped on the cable. I should mention that my meter seems to be acting funny and I am not trusting the amp readings 100%, because sometimes when I would take the clamp back off the battery cable, it would still read 1 amp without being clamped on anything and not even being near the cables. When I would open the clamp but keep the clamp over/around the cable, the meter would immediately go up to 2.5 amps, and then when I would close the clamp around the cable again it was going back to only 1 amp.

Either way, I definitely have a parasitic draw, since the test light method is clearly confirming that. But I just can't find the source of the draw, since pulling every fuse never turns off the test light.

Thanks so much for your input!
-Ben

 

[crash68]

If the battery is about 4 or more years old, probably start by replacing the battery

 

[jillshubby]

Thanks for your input. The battery is about 4 years old. I will go ahead and replace it and go from there.

 

[Runaround]

Have your battery load tested. The slight draw could be coming from the computer.

 

[CanuckRam1313]

Thanks for your input. The battery is about 4 years old. I will go ahead and replace it and go from there.

Perhaps also look to the H8 battery upgrade, and then take that one step higher and go with an AGM battery, too.

 

[RamDiver]

Perhaps also look to the H8 battery upgrade, and then take that one step higher and go with an AGM battery, too.

Living in Texas, I wouldn't expect the battery to last more than 2 or 3 years.

If Costco has the same 4-year replacement warranty as our Costco Canada does, the AGM might be a smart choice.

.