2013 CMax Hybrid SEL AGM battery?

[plus 3 golfer]

...

 

Still baffled by all this, even with Plus 3 Golfer's gracious detailed explanation. (Truth be known, I really have no idea what the SOC is on an ICE 12V battery, but thinking the alternator keeps it hovering in the 60-80% range, maybe nearer to 90%, never 100%. All I know is, with a healthy ICE 12V battery, an overnight BatteryTenderPlus charge will bring it to 100%)

...

 

It just may be that the way our 2013 CMax is now being driven is a pattern that depletes that 12V battery. Sounds weird, though!

I have been doing some digging on the BXT line of Motorcraft batteries which are made by Johnson Controls. It appears that the BXTs are likely an Enhanced Flooded Battery.  The EFBs are a battery design between a standard flooded battery and an AGM battery.  They are designed to operate at low state of charge and have cycling capability (primarily for ICE start / stop applications) like my mini cycling theory in a previous post.  They have systems that reduce acid stratification with normal car movement. Stratification increases sulfation and battery failure. By reducing sulfation, an EFB does not have to be fully charged periodically like a flooded battery.

 

 

I believe the C-Max battery is an EFB and thus Ford has designed the charging algorithm as I’ve seen and discussed for an EFB. This charging philosophy has benefit especially for the Energi in saving fuel since when plugged in the Energi 12V battery can be fully charged with AC wall power.  Attached are snips describing an EFB.

 

If the BXT is an EFB, we need to shift our thinking from a flooded battery to an EFB.

Edited November 21, 2019 by Plus 3 Golfer

[plus 3 golfer]

Xxx

Edited November 21, 2019 by Plus 3 Golfer

[pianewman]

Thanks again, Plus 3. Wow, your curiosity and diligence are astounding. Thank you.

 

Sadly, regardless of your diligence and excellent advice, we're still dealing with a parasitic drain issue, since the dealer tech (also very diligent) couldn't find the parasitic drain. Totally bizarre that the APIM came back to life as the Service Adviser was bringing the car out front for me.

 

Bottom line: my son just can't handle the very real potential of random battery failure. I don't blame him. We love the car: fit and finish, SEL level trim, handling, minimal road noise. We don't want to lose it, but we're moving in that direction.

 

FYI, put the BatteryTenderPlus on the battery last night. It took 2+ hours to come up to 80%, and overnight to reach 100%/float. If, in fact, it is an EFB, all of that is moot, though.

[plus 3 golfer]

Yep, doesn’t matter what battery you have, if there is a parasitic drain.  The C-Max Hybrid charging algorithm makes sense for an EFB but not so much for a standard flooded battery.  Also, The 100 month prorated warranty on the BXT Max makes sense now since heat has less effect on EFBs.

 

So, perhaps the drain is gone for good as car charged on the tender. Maybe give the car another few months??  :stirpot:

Edited November 21, 2019 by Plus 3 Golfer

[ptjones]

To me it would seem to make sense to have a small battery jumper and stop worrying about the battery. If it goes down just jump it, takes a minute to do and you are off to the races. :)

 

Paul

[pianewman]

 

Yep, doesn’t matter what battery you have, if there is a parasitic drain.  The C-Max Hybrid charging algorithm makes sense for an EFB but not so much for a standard flooded battery.  Also, The 100 month prorated warranty on the BXT Max makes sense now since heat has less effect on EFBs.

 

So, perhaps the drain is gone for good as car charged on the tender. Maybe give the car another few months??  :stirpot:

 

Sigh...don't want to deal with "perhaps:" 

FYI, the replacement battery (batteries) that the dealership is selling me (in the $140 range) are warranted for 4 years full replacement, 2 years prorated, IIRC.

 

Another FYI: I phoned BatteryTenderPlus today (Deltran), and inquired about info regarding the BTP use with an EFB. HAHA! He had never HEARD of EFB!!! Sorta kinda changes my perception of BatteryTenderPlus!

 

[pianewman]

To me it would seem to make sense to have a small battery jumper and stop worrying about the battery. If it goes down just jump it, takes a minute to do and you are off to the races. :)

 

Paul

You clearly aren't a 21-year-old young man...HAHA!. I've tried my best to instill my "hand-on" attitude about household plumbing, landscaping, car maintenance, household electrical, etc. etc. All we've managed to do is instill a very strong musical work ethic, and he has excelled, in the jazz program at UNT, graduating in 3 years, now a grad asst, with his own lab band.

 

SOOO...we're cutting him some slack. Wish he could do it all, but...

 

...appreciate your advice. I totally agree with you, but I've got to pick my battles!

[plus 3 golfer]

You can use a normal battery tender / charger with an EFB. It's still a flooded lead acid battery. I don't believe your are getting the Motorcraft BXT67R MAX battery which Ford has a special price (IIRC to the end of the year) for $129.95 around $10 to install and its warranted for 3 years full replacement and 100 months prorated. 

 

See below as the BXT Max sounds like it has similar attributes (technology) as an EFB.

• Long-life alloys and optimized grid design provide excellent performance over conventional designs in high-heat conditions
• Envelope separators help reduce and add to battery life
• Motorcraft® Tested Tough® MAX (BXT-Line) state-of-the-art technology enhances battery longevity and reduces recharging time

https://www.motorcraft.com/us/en_us/home/new-old-our-products/batteries/motorcraft-tested-tough-max-batteries.html

Edited November 22, 2019 by Plus 3 Golfer

[pianewman]

Just checked my receipts. I guess we WERE getting the EFB

12/28/18...BXT67R, at 82k miles

 

9/27/19...BXT 67R,  at 97.5 k miles

 

Battery dead, 11/13/19, at 100k miles

[pianewman]

Good morning, y'all. I hope you're having a great day!

 

My CMax is totally dead again this morning. AND...GRRRR...the mechanical key the dealership cut for me, and sold to me, doesn't work in the door.

 

So...my fancy lithium jump charger is worthless.

 

Have...a...nice...day...!!! :)

[plus 3 golfer]

So, neither of the FOBs have the key inside?

 

Even though the APIM may be OK once you get the car started, I’d pull F79 and leave it out or at minimum leave the cover off the BCM fuse panel and pull F79 each night and replace when starting car.

[SnowStorm]

I know your dealer said CSP 15B04 doesn't apply but I still wonder about it and possible wire chaffing that is mentioned therein.  The CSP says "For vehicles built on or before June 3, 2013, inspect wiring in specified locations for damage and/or chafing and repair as needed."  When was yours built?  I know chaffing can kill batteries - I once had an SUV with aftermarket trailer wiring where a wire was run from the battery to the back.  It went over the rear open axial where it eventually rubbed through and would kill the battery (without blowing the fuse!) while I was at work.  Very intermittent.  If they haven't, perhaps your dealer would check for chaffing per 15B04 anyway.  The pictures and instructions in above link seem pretty clear.  This whole 12V battery thing is insane.

[pianewman]

Uhh...well...I don't know how to say this, but, I screwed up. My previous post claiming my CMax battery was dead again was totally incorrect. I apologize for my error.

 

When my wife went to drive the CMax, she said she couldn't get into the car. She took our Leaf instead, handing me the key. In the confusion, when I went to check on the CMax, I used the key she handed me, and...well...it...was...her...FUSION KEY!!!!!!  Obviously, it wouldn't work, nor would the metal key inside the fob.

 

I didn't discover my error until later in the day, after posting here, and calling my dealership to complain. I phoned the dealership as soon as I could, to apologize.

 

So, the CMax is functioning just fine, which is pleasing me.

 

Sorry for the confusion. I feel like an idiot. 

[SnowStorm]

Glad to hear its still running - and don't be too hard on yourself, I think we've all done something similar, I know I have.

But it does suggest a marketing opportunity for Ford - "one FOB to start them all"!

[pianewman]

The comic relief of the incident had us all shrieking with laughter, especially since I have a family history of, "...never doing anything wrong..." I'm the Mary Poppins of the family, "practically perfect in every way."

 

Another FYI for y'all.

 

Drove the Cmax, 80miles, several stop/starts. APIM functioning. Plugged it into BatteryTender, fully charged after 7 hours.

 

Russian roulette, for sure, awaiting the APIM failure/subsequent battery drain.

 

Also FYI, trade-in offers of 4k to 5k, on used $17-18k cars.

[plus 3 golfer]

Glad you can laugh at the key fob mixup now.  
 

It’s still puzzling how the APIM died and then came back to life.  There’s no telling what the tech may have done investigating the drain issue during / after the APIM supposedly “died.” Did the dealer investigate the lift gate issue also? Perhaps jiggling enough wiring, reseating / cleaning connectors and so forth got rid of the drain.

 

For all, I just completed driving about 2100 miles (just under 31 hours driving time) from Phoenix to Pittsburgh and monitored the 12 V battery charging.  I started at 37% SOC (dropped from the normal low 40s because I was in ACC mode for a while while I re-trained the TPMS sensors and adjusted tire pressure just before the trip).  I ended the trip at 66% SOC which is likely very close to my maximum charge for a my nearly 54 month old battery.

 

I validated that 12 V battery temperature affects the charging algorithm.  I don’t know the exact details but it’s clear that the set point voltage which is calculated by the PCM and used by the DCDC converter changes.  See the Battery University temperature adjusted snip below.  At ambient around mid 30 F, I saw set point voltages at 15.0 - 15.1 V (according to SM the maximum).  At mid 50 F, I saw set point voltages around 14.7 - 14.8 V.  So, basically, the charging current remains virtually the same whether the battery was warm or cold vs time on charge, current SOC and Ah of losses.  It appears that the charge (Ah) into the battery would be virtually the same regardless of temperature. 

 

I also want to point out that when we talk about SOC and use voltage measurements as a proxy for SOC, that one should adjust their voltage reading for temperature which are not around 80 F and should use the following voltage adjustment from Battery University.  Otherwise, we can’t compare an actual reading of 12.14 @ 90 F vs 11.96 F @ 30 F without knowing the ambient.  Based on the 0.024 V per 10F, the charge in both batteries is virtually the same.

 

“Battery Voltmeter Temperature Correction using Addition and Subtraction

In this method you use the standard State of Charge versus Volts Chart.  Remembering that the battery voltage will read lower in colder weather and higher in hotter weather, you simply…

• Subtract 0.024 volts for every ten degrees F, if the temperature is below 80 degrees F.
• Add 0.024 volts for every ten degrees F, if the temperature is about 80 degrees F.”

Edited November 26, 2019 by Plus 3 Golfer

[pianewman]

I've solved my 2013 CMax SEL APIM/battery drain problem: traded it for a 2018 Toyota Prius Two.

 

Loved the CMax, but at 100k miles, with a sloppy suspension (prob needed struts/stabilizer bar ends) and a totally unpredictable, random battery drain, and a worthless, unwarranted APIM replacement pending ($1k), we just couldn't justify keeping the car. I no longer have any interest in fussing over any of my 4 cars!!!!

 

For sure, the CMax MUCH is more well appointed than the Prius Two, but the Gen 4 Prius has finally solved the "weird" suspension/drivetrain issues of previous generations. Throttle input is very linear, Elec/ICE transitions exceptionally smooth, ICE not nearly as rough as before. It'll never be a real "driver's car." That's very clear.

 

Oh...and the the 58-62mpg my son is getting, w/o serious hypermiling, makes us smile.

 

Keeping our 2017 Fusion Energi Titanium for the time being, mostly because trade-in value is totally unacceptable ($12k, while the same dealer sells them for $18.5k!!!!). We really love the Fusion, as well, and hope we won't be chasing electrical issues. Needed a replacement 12V battery at 30k miles (seriously???), hoping the replacement lasts longer.

 

Thanks for all the advice here. I learned a ton, but sadly, won't be putting it to use on the 2013 CMax!

[SnowStorm]

Considering the car problems and your driving needs - I'm not about to blame you.  Improvisation belongs in Jazz, not transportation!  Best wishes for the Prius and your son's career.

[stratosurfer]

I read all these problems and have to feel that the early years (2013-2014) were a mixed bag of QA at Ford and the CMax. On the one hand mine has been relatively maintenance free throughout 144K miles and nearly 7 years. Of course I did put just under 3K in a salvage HF35 transmission swap out. I’m doing the sync 2 to 3 mod/upgrade in the next couple of days even though my sync 2 system is all functioning again after the fuse reboots, I really need Apple CarPlay for my long commutes. I think after this I will have a car I’m quite comfortable in maintaining and frankly keeping for the longer haul as the major issue of the HF35 transmission is done. As has been mentioned the soft market on selling these against the value I realize in commuting 1000 miles monthly, and towing... I can’t imagine anything can fill the bill as efficiently.

Maybe the Cybertruck...

[SnowStorm]

On 10/5/2019 at 11:47 AM, SnowStorm said:

Should have kept my mouth shut as we just had another bead battery. :rant2: Car had sat in the garage for about 8 days, being moved from one bay to the other about half way through this time, then its dead - no lights or anything.  Jump starter brought it on immediately.  I didn't have my meter handy so don't know how low it was.  So much for "the fix".  ? Went for a 40 mile round trip yesterday and it was fine, and OK this morning.  Driver's window was down part way when it went dead so now the bounce-back and auto-close functions are messed up.  Now I have to figure out that fool thing.  I guess we have to go for a drive every day and reconnect my old battery alarm.  Problems with this car are getting older than the car. :sad:

Now another dead battery!  Backed car out of garage in EV mode a few days ago and turned it off.  Loaded stuff and after maybe 30 minutes or less went to open hatch and no response.  Remote lock/unlock dead.  Got in and tried to start - everything was dead, no lights or anything.  Checked the voltage under the hood and got 7.36 volts.  "Jumped" it and went on our way.  Not good.  It looks like I'll have to build a real monitor for both voltage and current when car is off.  Or maybe I'll just have to leave the car on all the time it is parked!  But that means an exhaust hose from car to outside the garage!  What a pain!

 

The car has sat for a day now so I just checked the voltage.  It was 9.9 volts and over  a few minutes has gone up to 10.2 volts (opening the door turned stuff on and pulled the initial voltage reading down, no doubt).  Its gone!  Totally disgusting.

[SnowStorm]

Continuing from previous post:  car has sat overnight without starting or opening any door.  Voltage at 10.37 volts.  Opened driver's door for a few seconds and closed it.  Reading dropped to 9.00 volts then stepped up as things turned back off (you could hear relays clicking) to 10.0 volts.  The battery is discharged and the voltage very sensitive to load.  This activity highlights the insidious nature of the problem.  I could, no doubt, have started the car and gone on without being aware of any problem.  This scenario could happen many times until one day the voltage is a bit too low (maybe below 8 volts?) and your stuck with another dead battery.  The problem is, the battery was "dead" many times before, just not quite low enough to prevent starting.

Edited January 4, 2020 by SnowStorm

[SnowStorm]

Hooked up the automatic charger this morning and set it to 2 amps.  After about 4 hours it shows 100% charge and 15.9 volts.  If it really got to 100% and if it put out 2 amps all that time (doubt it), that would only be 8 amp-hrs.  Again, battery appears to be shot.

[fbov]

Too bad we can't trade chassis; I'll likely trade mine in with the original 12v battery and the original tranny. Love the car, but in the 18 months between trying to purchase the last 2018 C-Max, and succeeding with a 2020 Escape, the trade-in value dropped 25% at 65K miles.

Frank

[SnowStorm]

So, my dealer tested my 12v battery (it failed) and installed a new BXT-67R for a grand total of $59 since over half of 100 month warranty remained.  They reset the age monitor without my saying anything about it.  At home Forscan showed age at 0 and SOC at 95%.  Sure hope this one lasts until I get that VW ID.Buzz!

[jzchen]

On 1/9/2020 at 4:21 PM, SnowStorm said:

So, my dealer tested my 12v battery (it failed) and installed a new BXT-67R for a grand total of $59 since over half of 100 month warranty remained.  They reset the age monitor without my saying anything about it.  At home Forscan showed age at 0 and SOC at 95%.  Sure hope this one lasts until I get that VW ID.Buzz!

 

Resetting the battery monitor is part of the instructions.  Glad they did it.  When I replaced our ex Energi's battery at about 3 years I did not reset for 1 day, while I figured out how, but I honestly didn't notice a difference...