UPDATE: Thank you everyone who helped! The issue in the end was the alternator after spending several days on getting it fixed. Thank you so much for your help!

I have a 2014 Dodge Grand Caravan R/T. Recently, my battery light warning would pop-up as I was driving and then go away after turning off my van. When I tried to have a mechanic test it out, they said they can't do anything to find out what is really wrong with it until the warning light came back. The problem is, every time I would turn off my van, the light would go away.

Forward to this week, my battery was dead. I got it jumped and took it to Advance Auto Parts where they said my battery was good and only needed a recharge. They did say that it's my alternator draining my battery giving me the issue although I don't remember them doing a test for it. When I took my van to a trusted area mechanic today, they informed me that they it could be electrical as well without taking a look at my van. They also repeated what my previous mechanic informed me concerning if the issue was my alternator; that they couldn't really tell if it was the alternator unless my van's warning indicator came on.

So what should I do at this point because I'm getting pointed in a lot of directions and not so sure what to do? Should I drive my van and hope that the warning indicator comes on and take it directly to the mechanic or should I take it to the mechanic and have them do a diagnostic on it without any warning indicators? Or should I just go ahead and replace the alternator?

Help! I have a lot of trust issues as a different mechanic screwed me over by destroying a previous van of mine (long story) so I am getting paranoid by the second.

 

Per Dodge's service manual, the charging system output is controlled by the PCM and calibrated to stay within a range of about 12.0 to 16.0 volts. The warning indicator is PCM controlled and will only come on if the system voltage is outside of this range.

Generally speaking, when alternators begin to fail, it's because they're not able to produce enough voltage/amperage to properly charge the battery as well as run the electrical systems on the van. This tends to be a consistent problem rather than an intermittent one, which leads me to think the alternator is probably not the issue. I think it's your battery.

I know Advance Auto told you the battery is good and just needed a charge, but the problem with that is the battery has to be fully charged in order for a proper load test to be done. Auto parts stores will fast charge batteries in order to test them, but that doesn't allow for a complete and proper recharge, it only charges the battery enough for their machine to test it. The other problem is that, often times, bad batteries can test good.

The only purpose for the battery is to provide enough power to start the engine - once that is accomplished, the alternator is supposed to take over powering the electrical systems and recharge the battery. But if the battery is failing to take a proper charge, it creates a drain on the power output of the alternator, which then pulls power from the other electrical systems. I think your battery is in the process of failing, which is why you're still able to start the van without a problem and getting an intermittent warning light.

Try to pay attention to whether or not specific conditions trigger the warning light. Things such as:

-Extended driving time (more than your usual daily routine)
-Use of accessories such as radio, navigation, AC, windows, onboard DVD player, etc.
-Exterior lights on or off

If you can narrow down what conditions cause the light to come on, you can communicate that to your shop. That will allow their techs to trigger the light by mimicking the conditions which will give them a chance to diagnose the issue.

 

When a battery warning light comes on while driving it means that the alternator isn't charging and you're running off your battery. There's no doubt the likely culprit is your alternator in today's modern cars an array of diodes in some zener diodes are part of the internal voltage regulator circuit of the alternator. These diodes can go bad when they do they can created unfamiliarized weird problems. It could likely just be a thermal breakdown that's happening in one of the component that fails when it gets hot (warning light) then after you shut down your van it's good again till the next episode. Alternators can easily be tested with a multi-meter with engine running voltage across the battery terminal should be between 13.8 to 15.2 volts. Try to get it to happen again and just get it checked out without shutting off the van if you can't do it yourself.

Battery can also be tested with a load tester.

 

Thank you! I am driving it around today to try to get the light to pop backup so I can take it straight to the mechanic. I really apperciate everyone for putting my mind at ease!

Also, I should have mention that my battery is only 2 years old so that's why I wasn't considering the battery.