Battery Voltage

What is the battery voltage you guys have seen after leaving your car sit over night? Mine is usually around 11.2 - 11.4 seemed to be about the same even when it was warmer outside. I'm concerned there might be some problem and would just like to compare.

My concern started from every time I would hook a programmer up to the vehicle it will not let me proceed because the voltage has to be at least 12V. Not that it recommends I hook it up to a charger, it requires it. I've programmed lots of other vehicles and the recommendation is always there to hook it up to a charger but I've never had it not allow me to do anything until it's hooked to a charger.

When I drive the car, it goes right to 14.4V so I'm thinking it's probably not the alternator, most likely the battery just isn't holding the charge well. The surprising thing is it's a 2015, 3 years old and it's always been this way and I've never had a problem with the car starting, not even on the coldest winter mornings.

A voltage of 11.2 - 11.4 just from sitting over night is too low. Check it across the battery itself to verify the gauge is semi-accurate. Usually the dash gauge reads about 0.5 volt lower than across the battery terminals.

The voltage on mine will be around 12.4 across the battery after sitting 2 weeks. The batteries in these cars are kind of weak. Pop the caps off the top and look at the electrolyte level. I had to add distilled water to mine only 1 year after the car was made. I keep my battery charged on a Battery Tender over the winter storage months.

GT Pony said:

A voltage of 11.2 - 11.4 just from sitting over night is too low. Check it across the battery itself to verify the gauge is semi-accurate. Usually the dash gauge reads about 0.5 volt lower than across the battery terminals.

The voltage on mine will be around 12.4 across the battery after sitting 2 weeks. The batteries in these cars are kind of weak. Pop the caps off the top and look at the electrolyte level. I had to add distilled water to mine only 1 year after the car was made. I keep my battery charged on a Battery Tender over the winter storage months.

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I checked it across the battery and it was much better, 11.97. I'm still thinking that's a bit low but like you said, over .5V difference from what the computer was reading. Ford says the battery is fine but I'm not sure I want to trust it for another winter. I didn't get time to check the water levels, hopefully I can get to that tonight. That might make all the difference.

Ive been thru this recently on my 15 if I can add to definitely check the battery water/electrolyte level, my car did not have a sealed maint free battery and not knowing this and the battery being under the cover such as it is, I never saw this or checked it. Incidentally ran the battery dry, refilled it, but it was never came back after several chargings. Would be OK for 1-2 days before it went to slow cranking. Replaced the battery and all is well now.

There's a lot of parasitic load on these cars. To get a true read on the battery voltage you'd have to take the ground off the battery and let it sit for a while with zero loads then test it with a voltmeter. I found my battery was below 12 volts in 2 weeks when in storage and hooked up. Now I just take the ground off for the winter, in cold weather the battery self discharges very little. Top it off once or twice during winter and it's fine. Of course it does the re-learn stuff and you have to reset your radio and so forth, but that's no big deal for me anyway.

What replacement batteries have you all been using?

Thanks again for the heads up. I checked the water levels and sure enough, the outer 2 cells of the 6 were just below the top of the plates. Now they are all just over the top of the plates.

FYI, If you fill your battery over the winter, you really should put a charger on it. Water itself is not good for the battery. I can't say all the technical details but charging it changes the properties of the water, then it's ok. Hope it helps.

I think my battery is just weak. After a trickle charger over night (didn't check the voltage before I started the car) and a 25 minute drive (20 minutes highway, 5 mins surface streets) it was as usual at 14.4V for the drive. After about 15 minutes I got back in the car and before starting again, it was at 11.4V on the dash. After the same drive home, I shut the car off then immediately just turned the car on (KOEO) and again it read 11.4V. That is really about 11.97V with a voltmeter across the battery. I still think that's a bit low. I think it should be 12.5-13V. Maybe those 2 cells being low for a while damaged it.

jbailer said:

I think my battery is just weak. After a trickle charger over night (didn't check the voltage before I started the car) and a 25 minute drive (20 minutes highway, 5 mins surface streets) it was as usual at 14.4V for the drive. After about 15 minutes I got back in the car and before starting again, it was at 11.4V on the dash. After the same drive home, I shut the car off then immediately just turned the car on (KOEO) and again it read 11.4V. That is really about 11.97V with a voltmeter across the battery. I still think that's a bit low. I think it should be 12.5-13V. Maybe those 2 cells being low for a while damaged it.

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Yes, it should be around 12.7~12.8 volts across the battery after charging and driving the car that long. I think it's time for a new battery.

My battery has been weak from day 1. It has gotten worse now that the car is 3 years old.

IIRC, I usually see 11.4-11.6 before starting it. Lately it has been sitting at 14.6-14.7 when the car is running. It probably needs a battery soon.

I interpreted my voltage, wrong or right, when it was >14.5 and .6 that it was trying, too hard, to charge the battery because it was on it's last leg. Of note, too, in going thru this the little green "eye" on the battery, even if it's green, it's only reading one cell not all of them.

Yeah, I just noticed that I'm having the same problem as well with my battery. As Chef has mentioned, what are you guys replacing the battery with?

chowman90 said:

Yeah, I just noticed that I'm having the same problem as well with my battery. As Chef has mentioned, what are you guys replacing the battery with?

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I used to buy into the Optima (red top) hype but not after owning a couple. I'll either get an Interstate battery or a Sears Die Hard.

I think the spec was 660CCA and I just took whatever Battery Oreilly had on the shelf, works perfect so far.

VinnAY said:

I think the spec was 660CCA and I just took whatever Battery Oreilly had on the shelf, works perfect so far.

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Hmmm the Sears Die Hard and the Interstate batteries are both rated at 590 CCA, maybe I should look a little more.