Possible problem with 12V battery

[Noah Harbinger]

On 9/21/2020 at 3:07 AM, jestevens said:

Well I finally received my first unexpected completely dead 12V battery this last Saturday morning with the change to colder weather.  Luckily a friend was able to drive me to Autozone to buy a jump pack, I bought the small 800amp one and it worked.  I left the car running for about an hour to charge back up.  Thankfully the 12V still seems to be holding a charge -- we had another day of cold weather Sunday and it was still able to start.  Have no idea why it would have happened other than driving the car only about once or twice a week due to COVID.  The last time I had it out prior to that was Wednesday, where it had a nice 1.5 hour drive but I did have the headlights on.  I'll have to pull my paperwork for when I had battery changed last time, maybe it's longer than I remember.

 

The 12-volt battery doesn't do much when starting a hybrid - it doesn't have to crank a starter like in a conventional vehicle. When mine died (2018, 5 years old at the time) I happened to have a 12-volt sealed lead acid battery lying around from a computer UPS that failed, and even with minimal charge, that was enough to start the vehicle - at which point the high-voltage system supplied enough power to keep the 12-volt system up, so that I could drive to an auto parts store to get a replacement. 

[Dale]

For 12v battery drain problems you should check out CUSTOMER SATISFACTION advisory 15B04.  This is not exactly a recall and so may not be on recall list but this is the problem with a lot of the early C-Max vehicles like mine.  I bought 3 batteries in a row before finding this.  If you need to buy a charger to keep charging your C-Max you should look into what is causing the battery to discharge.

 

https://ford.oemdtc.com/1696/15b04-12-volt-battery-test-and-module-software-update-2013-2014-ford-c-max

 

[WhiteKnight]

There are two different battery metrics using ForScan. There is "days in service" and there is "age in months". Forscan is showing me that my days in service is 100 (correct, I replaced battery three months ago)) but I noticed that when I did the reset it did NOT change the age in months. So it Forscan is reporting that I have an eight year old battery with 100 days in service. This doesn't seem correct to me. It seems to me that the reset feature should be resetting BOTH metrics, not just one. Can anyone confirm what is correct?

 

[Zathrus]

Just had my 12V battery replaced today (was 7.5 years old). Battery Monitor was reset, and the "BATTERY AGE" ForScan value changed from 2751 days to 0 days. Note that the "BATTAGEBECM" ForScan value (for the High Voltage Battery -HVB) remained 93 months (as the HVB was not affected). 

 

So only the BATTERY AGE (corresponding to 12V battery age in days) will be reset. The BATTAGEBECM (corresponding to HVB age in months) will not be reset.

[Gourockian]

On 8/2/2020 at 9:18 PM, plus 3 golfer said:

No, that’s not a charger.  Look for a charger that is at least 5 A, 8 or 10.would likely charge alittle faster.  Make sure it is a fully automatic, smart charger. If battery voltage was that low, it will likely take at least 10-12 hours and maybe more to reach full charge.  A new Motorcraft battery has a capacity of around 43 Ah.  My battery is 5 years old and it’s full capacity is now around 28 Ah or about 64% of its new capacity after I fully charge it on my battery charger.

 

BTW, I always put tire and battery receipts in glove box so I can easily find them after 5 years.?

I very much doubt if a smart charger would work on a battery which is at 2.1V.  When first connected, it analyses the battery's condition and if below a certain voltage (around 9V), they won't charge.  I have to use a regular charger if my battery is really low, then switch to the smart charger. 

[shaynei]

So I had the battery go bad, 5 years old. Replaced and reset the BCM back to 0 days using Forscan. The SOC was still only 22%, the displays would power down after a couple of minutes to save power, I took it out for a run for nearly an hour and the SOC went to 30%. Am I missing something? I have ordered a battery charger and going to leave it to charge up. Voltage under driving is showing 14.6v

[Louis]

This was at the top of the post for this subject:

   We have a 2013 Cmax Energi that is about 6 years old. We bought it while Ford was closing out the 2013's and got a pretty good deal on it. When all this Covid crap started, I stopped driving it and it stayed in the driveway for over 3 months. Last month when I started driving to work a few days a week, the first time I went to start the car it was dead as a doorknob!  This has happened a few times, but normally after I jump start it, then drive it a bit, everything returns to normal. I just figured it was dead because I had not driven or started it in 3 months. Last week when I was going to take it to work, it was dead again.  I connected our portable charger to it to jump the battery, and it started. I only let it run for about 5 minutes or so as it was really hot outside, and did not drive it. After I disconnected the battery, it went dead again. This morning I went out and the car was dead again, and I put a multitester to the terminals under the hood where I attach the jumper cables to, and it registered 2.1V. After jumping and starting the car, I drive it for about a mile or so, and  after turning off the engine, the battery tested at 12.6V.   The car started and the electronics seemed to work afterwards also. I will see how it is later today, but my big question is, is our 12V battery going bad? We thought we had it replaced last year, but we cannot find the receipt. Last year we had an issue where the car was dead almost every time I went to start it, and even when it did start, some of the electronics in the car like the audio system and electric windows did not work correctly. I saw on another post how to get to the battery, but apparently to get the date on the battery it has to be removed, and I just do not feel comfortable doing that. Any ideas???

 

Yeah! Something strange lke this happens to my 2013 Cmax. Every few weeks, I wake up to a dead battery. I spoke with a couple of Ford experts about it and they told me hat the problem is a random parasitic draw. And that it is difficult to find where the draw is randomly occurring.   So I bought me a jump pack. After I jump the battery, the car works fine until it happens again. 

[cr08]

If the car was left to sit for 3 months untouched, you likely need a new battery at this stage. Being sufficiently drained for that long probably damaged it in addition to its age so it won't hold much of a charge on its own.

[SnowStorm]

Louis, it is likely that your car needs to have CSP 15B04 done on it (assuming it was never done) - read about it here.  See if you can get a dealer to do it, though I suppose you will have to pay for it now.  Many of us had this problem years back and this CSP seemed to fix most everyone's problem.  Your 12V battery will also need to be replaced, I expect, since the repeated discharges to a very low voltage damage the battery.  I doubt that sitting for 3 months is the root cause.