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Hey everyone.

In the last week, I have had an issue with my car starting. I have not changed anything to cause this.

I ran a diagnostic on my car, no codes, and I checked the Voltage Output via my OBDII scanner, and it's saying that with the headlights OFF, Radio OFF, HVAC OFF, it was making 14.9V at the Command Module.

I have a 4-1 cig plug splitter run to my back outlet, and a double USB, single plug run to my cup holder plug location.

The outlets turn off after departing the car, and any devices that run on battery, will idle on their battery and turn off in time.

I have been very careful to turn the headlight selector to off, and push the button to disable dome lights at departure, and come back after an 8 hour shift at work and it's dead.

With a jump, it starts just fine, it runs just fine(actually noticed a minute increase in MPG compared to before this started lol).

Can y'all help me confirm my thought of this being a bad battery?

Kevin
 

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Make sure your connections are good also, Clean up the terminals, if you see any green corrosion in the wires, its a good idea to replace the bad power or ground wires.

I had some starting problems a couple years ago and it was bad corrosion on the positive terminal.

But yeah the auto parts store will test your battery for you. A great place to buy one is Costco, seemed to be alot cheaper than any of the auto stores. ($80)

Good luck!
 

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Both posts above offer good advice. Battery load test & Charging System tests are both FREE at most car part stores.

Adding:
Old cars like mine have the cigarette lighter sockets as ALWAYS HOT and never turn off. Your 2014 might be same or different. I recommend you double check this OR temporarily unplug all power adapters (when you leave the car) until you figure out the exact problem.

Gd Luck
 

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one thing to check is the glove box light is off, as this is always constantly live, can you connect your scanner to forscan? as you will be able too see the state of charge of your battery and amps, but with the cold weather this is generally the time batteries start to fail
 

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Make sure all lights are off and unplug the bulbs if not sure, like trunk and underhood if the car has them.

Past that, the battery dying overnite is likely a bad one. No mention of how old the one there is but that plays into it too. A loadtest at the parts store should show it pretty quick.
 

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Those USB outlets use an electronic converter that is quite efficient under load but they and any indicator lamps on gadgets draw a baseline load that is not insignificant in terms of battery load. Anywhere from 0.01 to 0.1A.
 

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Do a proper charge of the battery. (disconnected battery terminals.)
Battery should read no less than 12.10Volts after 24Hrs. of resting after being charged fully with the car battery terminals off the whole time.

After a successful full charge, install cables back on. Test drive car.

Then unplug any 12v accessories from cigarette-lighter/12v-Aux port.
Then check voltage again after shift of Work or 24Hrs. rest period.
Voltage should still be no less than 12.10Volts at rest.
 

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I would insert 12.3 instead of 12.1 volts in that last post to be much more correct. I used to test batteries by the hundreds and one thing you figure out pretty quick is that many cars in all brands start to have troubles at 12.2 volts or lower there after the sit. I worked out 12.3 as the best lowest number with zero issues. The good operating range is from 12.3 to 12.8 (brand new).
 

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Thanks, amc49.
I’m familiar with those numbers too, I’ve been working with 12V/24V lead acid systems for some time. I have to tip my hat to you for your quantity experience on batteries.
It’s good to meet others that understand these fickle batteries & the needs they have.

For Kprice8. If his battery has a healthy starting capacity, coupled with good clean contacts throughout the starting/charging system, along with a solid capable starter.
The battery will start the car with only 12.10 volts.
Abit weakly, but still does the job until battery “gives up the ghost” so to speak.

& yes it’s true.
Batteries with a minimal “disconnected” at rest voltage of 12.40V IS preferable, but not necessary.
It’s just wise to keep a lead acid battery happy at its 12.20-12.40V resting “connected” state. So one doesn’t become stranded, should the battery turn bad quickly…
 
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