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Battery Drain?

tsantsa

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Ok, I bought a 2020 GT Premium last year about this time. About a month after while cleaning the car, the car wouldn't start because the battery was drained. Jumped it, noted I needed to go get the battery checked...I am an idiot. Didn't check it. Happened two other times between then and this morning. Got to work and reset my oil light because the oil guy didn't do it yesterday (I realized it on the way to work). While going through the process, i just had aux power on and decided to fart with the menus a little. (Hey, I'm at work and it felt good to do this on the clock!). Car wouldn't start. Thankfully someone could jump me.

Went home and straight to Advance Auto. Battery good. Bought a battery jump pack because I REALLY wanna take the car on a road trip this weekend (Chicago area to Columbus Ohio). SO I decided to replicate the drain. I sat in the car, radio playing and playing with menu for 10 minutes...nothing. I kept the battery volt guage up so I could watch it. I got it down to about 12 volts but the car started....Tried again. This time (as I was getting fed up) I opened the door because it was getting hot with just the windows down...After a few secs, I saw the voltage dip! After maybe a minute it dipped again. I let it dip until some message about turning the car off came up. It did not start! I replicated it!

NOW! Does anyone know of a common battery drain problem with the doors open? The only thing I can think of is the overhead lights, but what would cause that???

Any thoughts?

(PS, also is there a way to pull up the TPS system in the menus? I had a low tire and wanted to see which one it was because I forgot which one when I cleared it while driving....)
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Cory S

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If it drained that fast from one moment to another, you have a bad cell in the battery. Basically, the reserve capacity of that cell is missing.
 

Nawsad123

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Your battery should read around 13.9-14.2 at idle...shouldnt see it fluctuate too much out of that range on a healthy battery
 

Cory S

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Do an over night rest test. Shut the car off and pop the hood. Test the voltage at the battery posts with a VOM. If it’s topped off good, it will read 12.5-12.7V. Let it sit 8-10 hours. Test the voltage the next morning again without starting the car or turning the ignition on. It should still be above 12.4V. If it’s under 12.3V, you may have a junk battery with a bad cell. If it’s under 12.2V, it’s definitely junk. For confirmed closure, let it go another 6-8 hours. If it’s dropped even further below 12V, battery should be replaced ASAP.

Test the alternator before you shut the car off as well. Test at the battery and voltage should be between 14.0-14.8.
 

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tsantsa

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WItoTX

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I 2nd bad battery. Do what Cory said. I have a post form two weeks ago where chased a drain. turned out it wasn't a drain, but the car pulling power for lights, and to prep the car for starting up. If you don't lock the doors and put the key away, the car will also drain the battery.

There are tons of posts on this issue, the search function is really good on this site.
 

#1ford

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Do an over night rest test. Shut the car off and pop the hood. Test the voltage at the battery posts with a VOM. If it’s topped off good, it will read 12.5-12.7V. Let it sit 8-10 hours. Test the voltage the next morning again without starting the car or turning the ignition on. It should still be above 12.4V. If it’s under 12.3V, you may have a junk battery with a bad cell. If it’s under 12.2V, it’s definitely junk. For confirmed closure, let it go another 6-8 hours. If it’s dropped even further below 12V, battery should be replaced ASAP.

Test the alternator before you shut the car off as well. Test at the battery and voltage should be between 14.0-14.8.
Fantastic analogy thank you for sharing your information
 

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KingKona

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Went home and straight to Advance Auto. Battery good.
What test did they do? Unless they pulled the battery from the car and bench tested it, you know nothing.

It's 99% assured that you need a new battery.

(PS, also is there a way to pull up the TPS system in the menus? I had a low tire and wanted to see which one it was because I forgot which one when I cleared it while driving....)
Seriously dude, read your manual. Or at least start flipping through the screens, learn about your car.

You go to the screen where all the diag parameters are displayed (temps, pressures, etc.), and then keep scrolling up. A new screen will appear with the tires pressures listed.
 
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KingKona

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Re: TPMS display, it'll show by using the up or down arrows from the trip/fuel screens.
I think it depends on the OPs car. For non-LCD screen cars (I'm assuming you have an LCD dashboard), it's not the trip/fuel screens, it's the vehicle information (temps, pressures, etc.) screen. You just keep scrolling up.
 
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tsantsa

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Ok will read manual. And find the TP screen.(I did look yesterday but it was vague…I have the digital dash btw)

what I don’t understand is why with the door closed I can have the radio blasting it doesn’t drain the battery, but the door open suddenly drains it….will have a bench test done on the battery if I can.
 

Farkel

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I think it depends on the OPs car. For non-LCD screen cars (I'm assuming you have an LCD dashboard), it's not the trip/fuel screens, it's the vehicle information (temps, pressures, etc.) screen. You just keep scrolling up.
Maybe I should have stated that my instructions pertain to the digital dash. Settings button --> trip/fuel --> up/down arrows to scroll thru trip1, trip2, tire pressures. YMMV
 

Torched10

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Maybe I should have stated that my instructions pertain to the digital dash. Settings button --> trip/fuel --> up/down arrows to scroll thru trip1, trip2, tire pressures. YMMV
Had similar problem.autozone load tested it and I gotta new sealed battery with 660cca for around 200 bucks installed problem solved
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