MFT Battery Saver message on shutdown

[bburzycki]

I assume this also has something to do with the overall issues people are seeing...

• Well here is the information from the Service manual - This is clearly an issue..
  
  This is taken directly from the 2016 Ford Utility Interceptor Service Manual **Also applies to civilian vehicle** regarding battery state of charge monitoring, external charger connections, jump starting and battery replacement:
  
  Battery State of Charge
  
  The BCM uses the battery current sensor to keep track of the battery state of charge. The battery current sensor is a Hall-effect sensor attached to the battery ground cable. During a drive cycle the Electrical Energy Management software adjusts the battery state of charge by monitoring the charge and discharge current and adjusting the state of charge up during charging, and down during discharge. During rest periods (key off with no electrical loads) when the vehicle enters sleep mode, the battery voltage is sampled to calibrate the State of Charge. The BCM automatically executes this calibration anytime the vehicle enters sleep mode and when the total vehicle current draw is below 300mA. It takes 8 hours in the sleep mode to calibrate the battery state of charge to high accuracy. If the system draw does not allow the battery state of charge calibration over the previous 7 to 10 days the State of Charge quality factor changes to flag this and some Electrical Energy ManagementFunctions which rely on the accuracy of the battery state of charge may be temporarily turned off until a calibration takes place.
  
  Battery Charging
  
  When charging the vehicle battery by connecting the charger to engine or chassis ground , the negative charger clamp must be connected to an unpainted chassis surface or a solid engine component such as a generator mount or engine lifting eye. In this instance, after charging, the BMS Reset is not required . Through this method of charging the BCM updates the battery state of charge during the charging process.
  
  When charging the vehicle battery by connecting the charger to the negative battery terminal is necessary , such as when using a combinationbattery charger and battery tester/analyzer, like the GR 1 190 V3.0 Intelligent Diagnostic Charger, the BCM does not immediately update thebattery state of charge. In this instance, the BMS Reset must be carried out using a diagnostic scan tool. This reset is needed for proper engine off load shedding and to prevent invoking of engine off load shedding earlier than normal.
  If the reset is not carried out, when the battery is charged by connecting the charger to the negative battery terminal, it takes approximately 8 hours for the BCM to learn the new battery state of charge. During this 8 hour period, the vehicle must be undisturbed, with no doors opened or keyless entry button presses. If the vehicle is used before the BCM is allowed to learn the new battery state of charge, engine off load shedding can still occur and a message may be displayed.
  
  Jump Starting
  
  When it is necessary to jump start the vehicle it is important to connect the cables properly in order for the Electrical Energy Managementsystem to measure the energy input to the system to keep an accurate state of charge. Connect the positive cable to the battery positive post and the jump start negative cable to a vehicle ground. Do not connect to the negative battery terminal. Connecting directly to the batterynegative post bypasses the ability of the vehicle to measure the input current, and does not adjust the battery state of charge accordingly. For a good connection point, follow the negative cable from the battery monitoring sensor to the vehicle body connection (typically on the shock tower sheet metal). If the vehicle was improperly jump started, the Electrical Energy Management system calibrates the battery state of charge after about 8 hours.
  
  Battery Replacement
  
  If the vehicle battery is replaced, it is very important to perform the BMS Reset using a diagnostic scan tool. If the BMS Reset is not carried out, it holds the old battery parameters and time in service counter in memory. Additionally it tells the system the battery is in an aged state and may limit the Electrical Energy Management system functions. For more information,
  Refer to: Battery and Cables - System Operation and Component Description (414-01 Battery, Mounting and Cables, Description and Operation).

 

[Greg Allen]

Fantastic! Thank you all.

I will print this and put it on the driver's seat when I bring it to the dealer. This way if the battery passes test, at least I know they will do the reset. I wish the dealer's would put the effort in forum monitoring to share information. It would save everyone time and money.

 

[Flatplane]

Gotta Love It when a plan comes together!
My point here is that "MOST" owners will not read the owners manual to resolve issues. Past that even more dealership technicians do not follow accepted standard operating procedure to resolve issues.
That leaves individuals to "trust" those sources of information that can be helpful and informative to acquire a resolution.

 

[Fred Klusmann]

Gotta Love It when a plan comes together!
My point here is that "MOST" owners will not read the owners manual to resolve issues. ....
That leaves individuals to "trust" those sources of information that can be helpful and informative to acquire a resolution.

Thank you for the information from the Service manual. I have saved a copy.
In my case the dealer took an owner's manual from another vehicle waiting for the correct one to arrive.
One of my requirements was that this be tow-able behind a motor home with 4 wheels down. The towing procedure asks for the battery (negative pole) to be disconnected - to keep feedback from sensors from awaking systems....
Problem: After reconnecting the battery, key fobs don't work, front camera and sensors fail, check engine lite comes on. The dealer has reset / re-programed everything, but scratches his head as how to prevent the loss in settings, or teach me how to do it.
I'd sure appreciate your suggestions.
Thank you.

 

[Greg Allen]

Sorry it took so long to get back. It's been lemon law crazy. I'll spare the details, but share the fix.
The wire harness to the gateway module (above the foot pedals) was chaffing on a bracket grounding wires to all 4 networks intermittently!!! They wrapped and re-positioned the harness to prevent it from coming back. This was absolutely insane!! There is surely a TSB to come. I recommend members here take a preventive look themselves. I'll try to add a picture. Thanks for all the feed back!!

 

[derfderf]

I assume this also has something to do with the overall issues people are seeing...

• 
  
  
  • Well here is the information from the Service manual - This is clearly an issue..
    
    This is taken directly from the 2016 Ford Utility Interceptor Service Manual **Also applies to civilian vehicle** regarding battery state of charge monitoring, external charger connections, jump starting and battery replacement:
    
    Battery State of Charge
    
    The BCM uses the battery current sensor to keep track of the battery state of charge. The battery current sensor is a Hall-effect sensor attached to the battery ground cable. During a drive cycle the Electrical Energy Management software adjusts the battery state of charge by monitoring the charge and discharge current and adjusting the state of charge up during charging, and down during discharge. During rest periods (key off with no electrical loads) when the vehicle enters sleep mode, the battery voltage is sampled to calibrate the State of Charge. The BCM automatically executes this calibration anytime the vehicle enters sleep mode and when the total vehicle current draw is below 300mA. It takes 8 hours in the sleep mode to calibrate the battery state of charge to high accuracy. If the system draw does not allow the battery state of charge calibration over the previous 7 to 10 days the State of Charge quality factor changes to flag this and some Electrical Energy ManagementFunctions which rely on the accuracy of the battery state of charge may be temporarily turned off until a calibration takes place.
    
    Battery Charging
    
    When charging the vehicle battery by connecting the charger to engine or chassis ground , the negative charger clamp must be connected to an unpainted chassis surface or a solid engine component such as a generator mount or engine lifting eye. In this instance, after charging, the BMS Reset is not required . Through this method of charging the BCM updates the battery state of charge during the charging process.
    
    When charging the vehicle battery by connecting the charger to the negative battery terminal is necessary , such as when using a combinationbattery charger and battery tester/analyzer, like the GR 1 190 V3.0 Intelligent Diagnostic Charger, the BCM does not immediately update thebattery state of charge. In this instance, the BMS Reset must be carried out using a diagnostic scan tool. This reset is needed for proper engine off load shedding and to prevent invoking of engine off load shedding earlier than normal.
    If the reset is not carried out, when the battery is charged by connecting the charger to the negative battery terminal, it takes approximately 8 hours for the BCM to learn the new battery state of charge. During this 8 hour period, the vehicle must be undisturbed, with no doors opened or keyless entry button presses. If the vehicle is used before the BCM is allowed to learn the new battery state of charge, engine off load shedding can still occur and a message may be displayed.
    
    Jump Starting
    
    When it is necessary to jump start the vehicle it is important to connect the cables properly in order for the Electrical Energy Managementsystem to measure the energy input to the system to keep an accurate state of charge. Connect the positive cable to the battery positive post and the jump start negative cable to a vehicle ground. Do not connect to the negative battery terminal. Connecting directly to the batterynegative post bypasses the ability of the vehicle to measure the input current, and does not adjust the battery state of charge accordingly. For a good connection point, follow the negative cable from the battery monitoring sensor to the vehicle body connection (typically on the shock tower sheet metal). If the vehicle was improperly jump started, the Electrical Energy Management system calibrates the battery state of charge after about 8 hours.
    
    Battery Replacement
    
    If the vehicle battery is replaced, it is very important to perform the BMS Reset using a diagnostic scan tool. If the BMS Reset is not carried out, it holds the old battery parameters and time in service counter in memory. Additionally it tells the system the battery is in an aged state and may limit the Electrical Energy Management system functions. For more information,
    Refer to: Battery and Cables - System Operation and Component Description (414-01 Battery, Mounting and Cables, Description and Operation).

THANK YOU!!!!

Having read through the entire thread, I have a few questions:
1) I am new to this gen of Fords (Saturns since 92) and I have never seen a vehicle droop it's own battery so badly on short trips. Sure, the batt is obviously not getting full alt charging output or this would never be an issue.

What I'm saying is that shouldn't a smart charging system be smart enough to recognize when the batt is in need of charging? Short trips using infrequently driven vehicles should be easily identifiable by the system if the algorithm is written properly even before you turn the key if the algorithm properly stored the pertinent data.

This sounds to me like a combination of:

1) The crappy 3 yr batteries put in new vehicles are a sin and WILL fail because they are likely the most inexpensive battery Ford can have built for them and private labeled. (To the poster who asked why they did not sell the car with a larger output battery-------it weighs 15 lbs more -- and that hurts fuel economy.

2) The algorithm is not written correctly in the sense that it should calculate based on driving habits (trip length, speed, distance, battery voltage) how much charge your vehicle needs before you turn the key. Start it up, and if it has not been driven, give it full alt charging output so that the battery is brought back to full health ASAP. Upon doing this 155 times, it should be smart enough to recognize that the trips are infrequent and the battery needs to be charged fully before its next shut down.

How do you ensure this? SUSPEND THE SMART CHARGING. Let the alt run full tilt and keep the battery at 14.4 running and hence 12.6V ish resting FOR THESE SITUATIONS.

I am all for lessening the impact on our environment. What I am NOT for is having to trickle charge a battery on a 5 yr old vehicle where 1/2 the reason the battery is bad is because the algorithm has kept it in such a lower state of charge that it's actually damaging the ability of the battery to recover enough to not need a friggin battery tender.

Sorry, but I call BS on this one......

 

[thefranchise713]

The batteries have quality issues but the charging algorithm is pretty smart.

Even with short trips these cars should have no problem maintaining proper charge. If it can't sufficiently charge, there is either a parasitic draw when the vehicle is off that is far, far out of spec or another similar issue.

When the vehicle is trying to replace the draw from the starter, if you monitor the BCM's Hall Effect sensor, you can see the amperage go through the roof to replace the energy lost from cranking. Once this is done, the charging algorithm tapers off the amperage to a more moderate level. Alternators are battery maintainers, they are not meant to be full-tilt chargers particularly for prolonged time. But in any event, Ford has been using this algorithm for several years and I have experience with it across several cars--its a great system.

As far as system voltage, it takes a trifecta of conditions for it to drop into the 12.6-7 levels. Most of the time (and I mean 95% or more) the system charging voltage will be 13.5 or higher, and especially in colder ambient temperatures, 14 and up. Charging will be less aggressive in hotter ambient temperatures if the charge is sufficient to keep the battery from cooking in hotter weather.

 

[peterk9]

I've had the 'low battery' message come up on both my previous 2011 Ex. Ltd. and my current MKT. As I've mentioned before, I attribute that to not driving the vehicle enough and the few short local trips I make, especially in the Summer months. Using a 2A trickle charge usually brings it back to full charge in about 8-10 hours. This Summer I decided not to bother with the charging for the last 2 months and experienced no issues except for the radio shutting down right away when the ignition was turned off and the message popping up. Finally put it on the charger the other day and now it should be good for 2-3 weeks before we get to the same issue again. I only have the vehicle for 7 more months and then I can start the whole thing over again with the new one.
The battery is a BXT65-750 (750 cca)

Peter

 

[derfderf]

PeterK9.:

It sounds to me like you are accepting this as the NORM. It is most definitely not the norm across the industry, and I am disappointed that you are willing to accept that this will begin anew with a brand new vehicle! Why accept this as the status quo?

Are you at least billing Ford for the initial cost, maintenance and electricity used by the trickle charger to maintain your battery in a sufficiently charged non-self-degrading state since Ford's smart charging algorithm can't seem to do that properly?

My sarcasm is not directed at you (I don't operate that way) -- it is directed at the sad silliness of the situation.........
--------------

The batteries have quality issues but the charging algorithm is pretty smart.

OK--Battery QC certainly sounds to be part of the issue. I agree.

So why after I don't know how long (recent 1st time Ford owner 2013 Escape) are people continuing to put up w crappy QC from Ford's supplier? More importantly, why is FORD continuing to put up with this from THEIR supplier? I don't doubt there are much higher $$$$ QC issues that will actually cost THEM serious money, not us, that take precedence. But that's not the point.

Even with short trips these cars should have no problem maintaining proper charge. If it can't sufficiently charge, there is either a parasitic draw when the vehicle is off that is far, far out of spec or another similar issue.

I agree these cars should be able to handle short infrequent trips and hold a charge. But unless I misread some of the posts, people are getting this message WHILE DRIVING, with the BCM shutting things off to conserve power.

Which means either
1) the battery is bad (I have had enough experiences w new car 3/36 batteries to know not to wait 3 yrs to change the first one
2) the charging algorithm is deficient in its capability to keep the battery properly charged under ALL reasonable use scenarios)
3) The alternator is not putting out sufficient current (as a function of time) when it is needed, either because the charging algorithm is not allowing the alternator to do so or the alternator is defective (backdrain through leaky diode, etc)

When the vehicle is trying to replace the draw from the starter, if you monitor the BCM's Hall Effect sensor, you can see the amperage go through the roof to replace the energy lost from cranking. Once this is done, the charging algorithm tapers off the amperage to a more moderate level. Alternators are battery maintainers, they are not meant to be full-tilt chargers particularly for prolonged time. But in any event, Ford has been using this algorithm for several years and I have experience with it across several cars--its a great system.

I certainly hope it can get that part right.
And I agree with you 100% -- alternator's job is to provide top off current to keep the battery charged AND to provide electrical current for operating the vehicle. What SEEMS to be happening here (no I cannot prove it nor am I stating this is is the only possibility) is that the battery is being charged but not fully charged.

I understand the whole point of doing it is to not charge very much more than you have been using, but also rapidly respond to changing charging needs. Less drag on the engine. But if you're harming the battery long term, then you just traded gas mileage savings for the cost of a new battery, plus the environmental impact of dealing with car batteries is not all that pretty.

If the charging algorithm "results" in a battery that triggers a low battery message to the driver, I must ask 2 questions:

1) What V is required to trigger this battery low warning message?
2) Is this V really all that low, or is the message a signal to the owner that the battery is no longer able to be charged within specs as defined by the algorithm?

If this was my first post to the thread and I had read no others, then I would guess 2) above.
But based on all of your hands on experiences, the battery CAN be charged into a state that allows for completely normal operations for weeks at a time.
------------
So is this a case of left hand/right hand silliness where the algorithm does what it thinks best, but the low battery message programming folks didn't talk with the charging algorithm folks and no one realized there is an overlap region where the two don't agree?

Most of the time (and I mean 95% or more) the system charging voltage will be 13.5 or higher, and especially in colder ambient temperatures, 14 and up. Charging will be less aggressive in hotter ambient temperatures if the charge is sufficient to keep the battery from cooking in hotter weather.

If this is the case, is this whole low battery thing a red herring? What's the avg rest V on these batteries? (I was referencing rest V not charging V in my previous post)
Is the low battery message simply an artifact of the way they are making the battery measurements for the algorithm????????

By the way, I often get passionate in my forum posts as I love a good discussion. Any disagreement I have or express is with the facts, not the person who posted them.
Please keep this in mind. I'm a mod on a diff forum so I "know better"........

 

[thefranchise713]

OK--Battery QC certainly sounds to be part of the issue. I agree.

So why after I don't know how long (recent 1st time Ford owner 2013 Escape) are people continuing to put up w crappy QC from Ford's supplier? More importantly, why is FORD continuing to put up with this from THEIR supplier? I don't doubt there are much higher $$$$ QC issues that will actually cost THEM serious money, not us, that take precedence. But that's not the point.

There is a small group of companies that make automotive batteries now. As for making sense of the business decision, I don't have an answer.

I agree these cars should be able to handle short infrequent trips and hold a charge. But unless I misread some of the posts, people are getting this message WHILE DRIVING, with the BCM shutting things off to conserve power.

Which means either
1) the battery is bad (I have had enough experiences w new car 3/36 batteries to know not to wait 3 yrs to change the first one
2) the charging algorithm is deficient in its capability to keep the battery properly charged under ALL reasonable use scenarios)
3) The alternator is not putting out sufficient current (as a function of time) when it is needed, either because the charging algorithm is not allowing the alternator to do so or the alternator is defective (backdrain through leaky diode, etc)

With a healthy (albeit drained) battery, the alternator output should be enough to maintain sufficient system voltage while driving. If it's engaging a load shed strategy, there is almost certainly a component failure somewhere. And it's probably the battery.

And I agree with you 100% -- alternator's job is to provide top off current to keep the battery charged AND to provide electrical current for operating the vehicle. What SEEMS to be happening here (no I cannot prove it nor am I stating this is is the only possibility) is that the battery is being charged but not fully charged.

You're correct. The battery is never fully charged--it usually hovers around 80% charge (per the BCM's estimate).

If the charging algorithm "results" in a battery that triggers a low battery message to the driver, I must ask 2 questions:

1) What V is required to trigger this battery low warning message?
2) Is this V really all that low, or is the message a signal to the owner that the battery is no longer able to be charged within specs as defined by the algorithm?

1-For engine running load shed, I think it's something like 11.5V for X time. My apologies, I don't have the workshop manual to check--that's from memory. If the voltage recovers I believe the engine running load shed message clears.
2-I don't think it means anything more than system voltage is less than optimal, and load is being reduced to preserve that voltage.

If this was my first post to the thread and I had read no others, then I would guess 2) above.
But based on all of your hands on experiences, the battery CAN be charged into a state that allows for completely normal operations for weeks at a time.
------------
So is this a case of left hand/right hand silliness where the algorithm does what it thinks best, but the low battery message programming folks didn't talk with the charging algorithm folks and no one realized there is an overlap region where the two don't agree?

The PCM and BCM seem, in my experience, to work well together. If you want to get a better idea on how this functions, get FORScan for your phone and a compatible ELM 327, and monitor state of charge, voltage, and current from the BCM. If you monitor the PCM, I think you'll be able to see duty cycle information as well.

Load shed when vehicle = off is a little insane in my opinion. 45 minutes of radio operation can trigger the message, regardless of State of Charge or voltage. And I think, again from memory, SoC below 40% or 10% loss when vehicle = off.
Load shed when vehicle = on seems to be on point. If it hits that point, given how low the voltage must be to trigger the load shed/warning, there is a serious problem--and at that point, the engineers are appropriately concerned about preserving the functions of power steering and the throttle body, among other critical components.

 

[derfderf]

So all these batteries of the posters above are dropping to 11.5V WHILE RUNNING? Eeek. That's less than a full charge on all six cells (on average).
But what is the charging system doing up to that recent point in time? Fighting it with full output to try to recharge up to 13.5 ish for x amount of time, realizes it isn't gonna happen, an spits out the battery low message? I assume it keeps trying, and, as you and others have stated, the message will clear.

So if the low battery V message ever appears, you're saying the vehicle is saying the battery is down to 11.5V (or whatever the V is)?
Seems that happens only if a batt cell is defective, high battery internal resistance, or substandard alt output for the given conditions.
Which then begs the question:

Is it a rectifier diode issue messing up the actual alt output V, a voltage regulator inside the alt not regulating per the requests from the BCM based on the algorithm?

I'm trying to rationalize how a fully "rugged" algorithm can fail to sufficiently fully charge the battery up every so often to ensure that the short trip infrequent driver doesn't need a batt tender.
Yet human intervention can get the charge and performance to a place where the car does not see the battery as low for a significant time. So then we circle back and ask "how did the battery get way"? Seems you could plot the SoC vs Time and see if there was a large change in slope somewhere -- could be during charging, could be while car is off....it'd be a start.

I just have a hard time believing so many bad batteries are ending up on dealer lots. Yes it happens.
Parasitic drain? That happens too -- or several systems interact in ways not previously considered to drain the battery. And starting batteries only have so many lives.......
------------
The original reason I joined this forum was to get assistance with a battery drain issue on a 2004 Explorer 4.0V6. Owner had already had mechanics do a drain test fuse by fuse,etc.
They forgot the alternator has an inline fusable link to the batt . That and they never ran a charging system check on it. Alt failed, rebuilt professionally. Works fine now. Wasn't until owner was about to reinstall that I figured out o4 had a smart charging system. Still don't know if there is a BSM type reset like the newer Fords...
------------

So how many of these low battery messages do you think are ultimately the result of bad alternators?
Some here have replaced batteries w MotoCraft, DieHard, etc, and STILL end up in the same place.
Yes there are more than three variables arnd it gets messy to try to draw conclusions.....still the repeat offenders w new batteries should be the easiest to isolate if data is captured and plotted from the very start..

____________________________________________________________________________________________________
Terminology ?: New to Ford tech stuff. BCM=Body control module or battery control module. I'm guessing the first.

 

[peterk9]

I have never had the message come up while the engine is running. It only comes up shortly after turning off the ignition and before the door is opened.
I figure much of it is likely due to the constant but low drain of the 'keep alive' circuits that these newer vehicles have. As I mentioned, this issue has happened with both vehicles and even after a battery replacement in the first one. It isn't a big issue for me as the batteries themselves have never failed or given any indication of possible failure.

Peter

 

[derfderf]

Thank you for correcting my factual inaccuracy. I reviewed a sampling of the posts in this thread and indeed the message is pretty much always right before shutdown. Which begs the question: The algorithm can't possibly predict wen you're going to pull over and shut off the vehicle. So why keep the batt charged to a V that is apparently terribly close to the V which triggers not only a low battery message, but shutting down of systems inside the vehicle to the annoyance of the driver?

The answer is ---fuel economy. Sounds like they keep the battery 895 charged (referring to previous post, which must be dangerously close to what the system considers problematic. The system does not know the difference between a real problem or presumably the result of it's own charging strategy.
If I am correct, this is a perfect example of running on the edge with partial disregard for the owner experience.

Seems like someone needs to tweak the algorithm or tweak the criteria for setting the message, because as it stands, if people are getting this message and it is NOT affecting startup but shuts down systems in the vehicle -- all in the name of fuel economy ---that's how you kill customer loyalty. GM is an expert at it. That's why I bought an Escape. I'm hoping Ford is not heading down that path.

 

[RGS1957]

I agree, this situation where the left has no clue about the right. I have never noticed any battery degradation, it's just very annoying. You're probably right, gas mileage. I've got a Jeep with start/stop, you can only shut it off at every startup. It's all about meeting CAFE standards.

 

[thefranchise713]

I'm not sure I follow your question...

Thank you for correcting my factual inaccuracy. I reviewed a sampling of the posts in this thread and indeed the message is pretty much always right before shutdown. Which begs the question: The algorithm can't possibly predict wen you're going to pull over and shut off the vehicle. So why keep the batt charged to a V that is apparently terribly close to the V which triggers not only a low battery message, but shutting down of systems inside the vehicle to the annoyance of the driver?

If you take a resting voltage, you'll find it likely to be above 12 volts and upward.

When the vehicle is running, the vehicle will aim for a system voltage of no less than 12.5 volts (my observation), and more often 13.5 or higher--95% of the time this is what you'll see.

The low voltage load shed message only comes on when running when it is far below the 12.5 observed minimum. (It may even be 10.5 instead of 11.5...I wish I still had my WSM access.) As for vehicle off, it's looking more at State of Charge than the voltage, even though you can derive the state of charge from the voltage, it's measured differently--tracking current usage.

Still nothing wrong with the algorithm in my opinion. As far as why it's never 100% charged, I believe that has more to do with keeping wear low on the battery. (Can't remember where I read that...) Remember, anything over 80% the BCM considers adequately charged and may engage the smart-charging strategy where it only charges the battery (substantially) on decelerations, maintaining a 12.5ish something system voltage otherwise until it charges (when it will spike voltage and current).

 

[derfderf]

I'm not sure I follow your question...


If you take a resting voltage, you'll find it likely to be above 12 volts and upward.

When the vehicle is running, the vehicle will aim for a system voltage of no less than 12.5 volts (my observation), and more often 13.5 or higher--95% of the time this is what you'll see.

The low voltage load shed message only comes on when running when it is far below the 12.5 observed minimum. (It may even be 10.5 instead of 11.5...I wish I still had my WSM access.) As for vehicle off, it's looking more at State of Charge than the voltage, even though you can derive the state of charge from the voltage, it's measured differently--tracking current usage.

Still nothing wrong with the algorithm in my opinion. As far as why it's never 100% charged, I believe that has more to do with keeping wear low on the battery. (Can't remember where I read that...) Remember, anything over 80% the BCM considers adequately charged and may engage the smart-charging strategy where it only charges the battery (substantially) on decelerations, maintaining a 12.5ish something system voltage otherwise until it charges (when it will spike voltage and current).

Ok

So are you saying that charging V's during use are high enough to be acceptable and to start the car?
I'm good with that.

But if that is true, why would the low battery message that comes on at shutoff is indicating the state of charge is too low? Or the batt V is too low? It's been charged sufficiently, no?

The contradiction of the above two statements is where I am hung up.

Why would a battery being charged at 13.5V throw a low battery V message? Is it the nature of HOW and WHAT information is being analyzed from the real time performance data to determine whether to throw the message at shutdown?

 

[bigdude2468]

2014 Explorer, 37,000 miles, exactly three years old. Today for the first time I am getting the "system off to save battery" message on start. Checked the battery and voltage is fine, do not have a way to put a load test on it. I put a charger on the battery and in roughly 10 minutes the charger indicated full charge. I used the vehicle yesterday so it is not like it had been sitting. In checking the owners manual it mentioned the save battery message does not necessarily mean the battery needs to be replaced. Any ideas?

 

[peterk9]

2014 Explorer, 37,000 miles, exactly three years old. Today for the first time I am getting the "system off to save battery" message on start. Checked the battery and voltage is fine, do not have a way to put a load test on it. I put a charger on the battery and in roughly 10 minutes the charger indicated full charge. I used the vehicle yesterday so it is not like it had been sitting. In checking the owners manual it mentioned the save battery message does not necessarily mean the battery needs to be replaced. Any ideas?

Your thread has been merged with this existing one found using the Forum's 'Search' feature.
I had this issue with my last 2 vehicles and usually after a month or so I'll put the trickle charger on it for 8 or so hours and wait for it to happen again, and again etc. Just wating now to see how long that new Platinum will take for the message to show.

Peter

 

[expoman55]

I just went through this very issue. My rid has 32k onit and is driven 50-60 miles every day. Additionally the serpentine belt started to squeal in wet weather. My dealer ONLY was able to find the battery was bad by running the ford diagnostic tool on my truck. when running the electrical tests. Then replaced the serpentine belt thinking it may have been causing a charging problem overall.
As a side note I had the message pop up about 8 months ago and it seemed like a fluke.
I think Peter is right check that battery.

 

[thefranchise713]

2014 Explorer, 37,000 miles, exactly three years old. Today for the first time I am getting the "system off to save battery" message on start. Checked the battery and voltage is fine, do not have a way to put a load test on it. I put a charger on the battery and in roughly 10 minutes the charger indicated full charge. I used the vehicle yesterday so it is not like it had been sitting. In checking the owners manual it mentioned the save battery message does not necessarily mean the battery needs to be replaced. Any ideas?

I would have a load test performed. It may not be holding voltage where it needs to be due to a bad cell, etc.