Battery, BMS , charging questions?

[SilverXLT6]

I go to start truck and it acts like battery is dead.
I put charger on 6 amp, go to check it 45 minutes later and it's already at 12.4V with charger off , it was 11.5V when I put charger on.
That seems too fast?
I remove charger .
Truck starts right up. I check voltage while truck is at high idle and it's over 14 volts.
Does a 2019 Ranger have BMS ?
Is the battery bad? What happened there?
IF I replace the battery do I need AGM ?
Will either a H6 or H7 fit ?
Is my charging system set to 70% ? Like this post says ? Will a Ford Tech change that for me ? :

" Our factory settings in the BCM have the charge capacity set to 70% of total capacity from factory "
Thanks!

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[Bsthroop]

Yes it does have bms factory set to 70%. If you are driving short trips the battery is not necessarily bad but may just be undercharged. Could have it tested after fully charging it. I replaced mine due to the same issue but turns out it is fine, so now i have disabled the bms with forscan- no further issues.

 

[SilverXLT6]

I'm charging it now on 2 amps. I'll let it charge all day and take charger off , let it sit over night and see what the volts are.
I never use stop/start.
I don't have Forscan and know nothing about it.
Thanks

 

[Frenchy]

If your battery is already at 11.5 without the truck running with no charger I can tell you that you have a bad battery. I don't remember the exact amperage right off but I do know the alternator on the Ranger is around 150. That is definitely enough to help charge the battery since the truck has the Auto start stop(even though many don't like the system). What do I recommend doing? Get yourself a new battery. Assuming you are already out of bumper to bumper warranty yout could try to use the extended warranty if you have that. If not buy a new battery from Ford or Batteries Plus and make sure the BMS reset is performed. The steps are available in the owners manual(careful, if you haven't opened it there.may be a bunch of cob webs).

 

[airline tech]

Check out my thread on this issue:
See if this matches your issues, 11.5 Volts the truck should still start, it should start with voltage down to about 10.2 or so.

https://www.ranger5g.com/forum/threads/mysterious-no-start-magically-starts-issue.26553/

11.5 Volts is the voltage where modules start to disable but still start.
BMS - is set to 70% on XL / XLT and 75% on the Lariats

AGM Battery only H6 for XL / XLT and H7 for Lariat- now the H7 will fit in all trims but the battery blanket if Original is H6 will not fit correctly over the H7.

If replacing battery you must do the BMS reset and also reset the Drivers Window -Auto function (up/ down)

No , the dealer will not alter any settings from OEM, so they will not change SOC or disable BMS

If you put on a charger it MUST be a charger with a AGM setting to properly charge, a standard charger can damage an AGM battery by overcharging / boiling the battery.

AGM batteries have a lower IR than Lead Acid - so they accept a charge quicker

 

[TJC]

I'm charging it now on 2 amps. I'll let it charge all day and take charger off , let it sit over night and see what the volts are.
I never use stop/start.
I don't have Forscan and know nothing about it.
Thanks

If you don't have or don't want to use Forscan to set battery charge rates to insure long battery life, simply unplug the BMS sensor on the negative battery terminal, charge the battery and forget about it.

11.5V doesn't necessarily indicate a bad battery, just a poorly managed battery being abused by a Battery Management System tuned for EPA mileage goals rather than battery health and long life.

There are 6 cells in a 12v auto battery. If a battery cell fails, you'll see a battery voltage in the 10V - 10.5V range. 11.5V indicates a severely undercharged and most likely a heavily sulfated battery.

Sulfation occurs when a battery is regularly undercharged. 70% SOC will always result in a 70% charge, and allows sulfur crystals to grow on the lead plates, which increases resistance, and slowly kills the battery. You then wake up one day with 11.5v instead of 12.65 volts and Ford makes money on selling you a new battery, which the BMS will promptly begin to kill as soon as you mount in your truck.

12.65v - 12.85v (measured after letting the battery rest for several hours) indicates a fully charged battery. Measuring just after a charge will give a false high charge rate. You must wait for the surface charge to dissipate to get an accurate reading. You really don't want battery voltage to drop below 12.5V. I think the voltages in the excerpt below are slight;y on the high side, but I posted this for reference. I think 70% SOC is somewhere around 12.4V-12.5V. I think 100% varies around 12.65V - 12.7V. Each manufacturer sets the threshold level. The real point is to keep the battery as close to 100% SOC as long as possible.

AGM Battery Voltage Chart​

Now, let’s talk voltage. Voltage is like the heartbeat of your AGM battery. It measures the electrical potential difference between the positive and negative terminals. In simpler terms, it tells you how much juice your battery is packing.​

​

When you measure the voltage, you’re getting a glimpse of your battery’s overall health and charge level.​

​

Here comes the exciting part! Let’s break down the AGM battery voltage chart. When your AGM battery is fully charged, it should show around 12.8 to 13.0 volts. Consider this the gold standard.​

​

But as your battery discharges, the voltage drops gradually. Don’t fret; it’s perfectly normal!​

​

State of Charge (SOC)​	Voltage Reading (Volts)​
100%​	12.8 – 13.0​
75%​	12.6 – 12.7​
50%​	12.2 – 12.4​
25%​	12.0 – 12.1​
Discharged (0%)​	Below 11.9​

Keep in mind that these readings are approximate and can vary depending on factors like temperature, battery age, and load conditions. Always refer to the manufacturer’s specifications for more accurate readings.​

Unplugging the BMS sensor on the negative terminal will disable the BMS system and charge your battery the same way previous generations of Rangers charged the battery. It is tried and true.

Be kind to your battery - unplug the BMS sensor, or use Forscan to disable ASS/BMS and set the SOC to 95% or 100%. Then you can forget about the battery and charging system.

Best of luck.

 

[underwhelmed]

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Are there any side effects from unplugging BMS sensor from the battery?

 

[dtech]

That's sound advice and don't be deterred by some who will create fud by saying the bms is responsible for charging your batt, in fact it mostly under charges it, and by design. Unplug the bms and be done with it.

 

[Capt Jon]

I'm charging it now on 2 amps. I'll let it charge all day and take charger off , let it sit over night and see what the volts are.
I never use stop/start.
I don't have Forscan and know nothing about it.
Thanks

The other good thing about Stop/Start is it will let you know if your battery is not charged up. It will not function. I just went about a month before my started working again because I was mostly taking short trips. AGM batteries are bad juju in my opinion. They are very voltage sensitive and don't work well on boats either. That is why I keep a fully charged jump starter in my Ranger.

 

[TJC]

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Are there any side effects from unplugging BMS sensor from the battery?

A healthy battery. And no ASS...

 

[TJC]

The other good thing about Stop/Start is it will let you know if your battery is not charged up. It will not function. I just went about a month before my started working again because I was mostly taking short trips. AGM batteries are bad juju in my opinion. They are very voltage sensitive and don't work well on boats either. That is why I keep a fully charged jump starter in my Ranger.

I had ASS disabled via the module that remembered the last switch setting of the ASS button. It does not interfere with any system, it simply presses the button for you at each start of the engine. I still had low battery warning come on.

I charged the battery, pulled the BMS plug at the Neg battery terminal, and I have not had a recurrence of the warning since.

Our Rangers have scores of microelectronic modules controlling all aspects of the drive train. These are digital systems that require stable input voltages and grounds. Voltage fluctuations will cause aberrations in system performance.

Walk into any data center, and notice the controlled environment, and the massive DC power supplies feeding the digital equipment as pure a voltage as possible.

Contrast that environment with your truck sitting in all manner of temps and humidity, with a bipolar charging system that is designed to maximize EPA targets over battery life, and you get the worst possible environment to be operating digital equipment.

It is nothing short of a recipe for disaster waiting to happen. ASS/BMS as implemented by Ford will result in early battery failure, and stress on the digital systems in your truck. All batteries will eventually fail, but why double or triple the failure frequency unnecessarily.

 

[Grandaccess]

If your battery is already at 11.5 without the truck running with no charger I can tell you that you have a bad battery. I don't remember the exact amperage right off but I do know the alternator on the Ranger is around 150. That is definitely enough to help charge the battery since the truck has the Auto start stop(even though many don't like the system). What do I recommend doing? Get yourself a new battery. Assuming you are already out of bumper to bumper warranty yout could try to use the extended warranty if you have that. If not buy a new battery from Ford or Batteries Plus and make sure the BMS reset is performed. The steps are available in the owners manual(careful, if you haven't opened it there.may be a bunch of cob webs).

more than once my Son has drawn mine down, he sits in my truck and does his Homework after school plays the radio and has the dome lights on, in the winter I put a battery Tender on it at least once a week, it wont get above 35F hear in N.Y until Apr.

 

[jmelair]

AGM Battery only H6 for XL / XLT and H7 for Lariat- now the H7 will fit in all trims but the battery blanket if Original is H6 will not fit correctly over the H7.

so here's a stupid question...

does the battery blanket actually do anything? From the ones I've seen, they appear too thin to actually insulate anything, add to that, the batteries are installed under the hood, which is all but exposed to the temperatures all the time anyway, I can't see it actually being any benefit

 

[Frenchy]

so here's a stupid question...

does the battery blanket actually do anything? From the ones I've seen, they appear too thin to actually insulate anything, add to that, the batteries are installed under the hood, which is all but exposed to the temperatures all the time anyway, I can't see it actually being any benefit

The job is to help keep a certain amount of heat from the battery and help the battery from getting too cold. How much it actually helps I can't say.

 

[Scottlane1171]

So if I up the battery threshold it will charge it more and this should help my stop start work properly?

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