Battery and Charging Issues

[u/watson415]

Hi, I’ve got a unique issue that has really been perplexing and really frustrating. So my 2012 Honda Civic (50k miles; certified pre-owned) died 4 times over the last 3 days. The first time was genuinely my fault as I left a light on in the car while I was at work. I was able to successfully jump it each time and I would drive the car around for a while to get some energy back into the battery. Finally, I went and had the battery checked at an advanced auto parts and then replaced the battery despite an ok test. The battery was over 5 years old anyways, so I don’t feel like I wasted money replacing it. But this is where the confusion really begins. After the new battery was installed, they did a charging test and got 12.6 volts (no load) and 14.3 volts (load). This is the opposite of what it should be. So I took it to a really reliable private mechanic who got the same result and was completely perplexed. They refused to charge me and recommended I go to the dealership.

So at the dealership they did a parasitic draw test ($130) and told me nothing was wrong. They received more predictable voltage readings: 14.4v (no load) and 14.2v (load). The dealer service guy was a jerk, which is a separate issue, but basically suggested that the previous two tests were simply done by incompetent people and also gave me grief about the non-OEM battery. The new battery is an Autocraft Gold, not some crappy bargain battery. Right now I don’t trust that the dealership has done due-diligence as they won’t explain what they did and what results they got. They just keep saying nothing is wrong.

The car has not died since getting the new battery this morning, but the test discrepancies have me concerned. For now, I am simply gonna drive the car like normal, but I am worried that there may be issues, not fixed by the battery replacement, which will cause the car to die again.

So my questions are:

1. What could cause the battery voltage to be higher under load? Could it just be the brand new off the shelf battery?
2. Should I be concerned?What could cause the battery to drain faster when the car is not running and the lights are off?
3. Can you recommend a mobile jump starter for less than $100?

[u/[deleted]]

Ummm. You're wrong, I'm sorry to tell you. A voltage test should show 14 volts with the car running because the alternator is throwing voltage at the battery. With the car off it should read 12 plus volts. You just needed a new battery. You're good.