low main battery
#26
MBWorld Fanatic!
Join Date: Feb 2014
Location: MA
Posts: 6,147
Received 1,503 Likes
on
1,174 Posts
2008 E350 4Matic, 2011 E350 4matic
I am having a tough time following this logic..."12.0v is fine and 10.5 starts a car" : your diagram shows 0% charged - how does that work?
Where you're a bit mistaken is: "your alt does all the work while the engine is running" - Nop not during accelerations when alt is OFF and AGM supplies 100% of consumers during the acceleration phase.
This is why I made a few recommendations above to prevent going Limp-mode at freeway/highway/autobahn speeds when exhausted battery shorts out... SOS.
😏
Where you're a bit mistaken is: "your alt does all the work while the engine is running" - Nop not during accelerations when alt is OFF and AGM supplies 100% of consumers during the acceleration phase.
This is why I made a few recommendations above to prevent going Limp-mode at freeway/highway/autobahn speeds when exhausted battery shorts out... SOS.
😏
The following users liked this post:
CaliBenzDriver (04-24-2021)
#27
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
out of sync!
Don't believe anything, just read the document posted earlier by Konigstiger. You will learn the reality of how the voltage management works on w212.
It works with different stages 14.9, 13.5, 12.6v managed by software pioneered by Bosch. Benz picked up this feature, just like Ford, Toyota, Kia.
✌️
#28
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
The following users liked this post:
Senecan (04-25-2021)
#29
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
The following users liked this post:
juanmor40 (05-27-2021)
#30
MBWorld Fanatic!
Thread Starter
so, NOCO was put on in AGM mode about 90 minutes ago and just now I went out there, top green light is pulsing slow (indicates its in the final charge stage), and my Fluke read 12.98V (which is a far cry from the 13.6 or so I'd expect at this stage, never mind the 14.x V for the 'absorption phase'
#31
MBWorld Fanatic!
Thread Starter
right, thats the at-rest voltage.... but the charger was running, so the voltage should be significantly higher than the rest voltage.... typically the end of the bulk phase of charging is when the voltage gets up to around 13.8V and the current drops towards zero, then the absorption phase boots the voltage to 14.8V or so (for an AGM) for a few hours to put that last 20% into the battery.
typical AGM charge cycle.....
typical AGM charge cycle.....
The following users liked this post:
CaliBenzDriver (04-25-2021)
#32
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
charging vs. resting voltage
so, NOCO was put on in AGM mode about 90 minutes ago and just now I went out there, top green light is pulsing slow (indicates its in the final charge stage), and my Fluke read 12.98V (which is a far cry from the 13.6 or so I'd expect at this stage, never mind the 14.x V for the 'absorption phase'
The outcome will be a fully charged battery. Until then don't worry about the time elapsed or voltage because ultimately that depends on the charge current.
It's not trivial to derive battery condition from resting voltage as it is not an exact science. There is a good chance your 2019 battery has more life given the care you're giving it.
Personally I hook up my CTEK in the trunk to charge the front AGM and measure AUX. The fat red cable comes from front BATT.
✌️
The following users liked this post:
Senecan (04-25-2021)
#33
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
15.6v BEWARE !!!
right, thats the at-rest voltage.... but the charger was running, so the voltage should be significantly higher than the rest voltage.... typically the end of the bulk phase of charging is when the voltage gets up to around 13.8V and the current drops towards zero, then the absorption phase boots the voltage to 14.8V or so (for an AGM) for a few hours to put that last 20% into the battery.
typical AGM charge cycle.....
typical AGM charge cycle.....
When reading the above graph you've noticed the high 15.6v used in the AGM mode to try rebalancing cells of deeply discharged batteries.
Electronic capacitors in this car (amplifier module and others) are rated at only 16V!!!
If you don't want to disconnect your battery from the car, I recommend you stick with regular non-AGM mode to preserve aging all the priceless electronic modules.... makes sense??
🙂
fancy Amp module 16v caps!!
Last edited by CaliBenzDriver; 04-25-2021 at 02:07 AM.
#34
MBWorld Fanatic!
Thread Starter
ok, so I for laughs went out there and got into the System Data menu while the charger was still charging...
short version:
and geezus, 9.6 amps drain just sitting there with a dome light on, but I did hear a fan or pump or something running.
short version:
- with the fob in the car and without stepping on the brake, push the Start button once, this is equiv to key position 1
- press the 'back' button on the left side of the steering group to get to the trip/odometer display
- within 5 seconds, press and hold the 'phone call' button on the right side of the steering wheel, then press the OK button on the left and hold it for 5 seconds. voila new menu!
- select System Data, OK
- up/down for lotsa stuff.
and geezus, 9.6 amps drain just sitting there with a dome light on, but I did hear a fan or pump or something running.
#35
MBWorld Fanatic!
Thread Starter
Electronic capacitors in this car (amplifier module and others) are rated at only 16V!!!
The following users liked this post:
YAOG (11-09-2021)
#36
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
so glad you got in... more power to you👍
Repeat the secret menu procedure before driving to keep an eye on the grumblings. You will see what goes on with your car after it completes its charge cycle ... go for an 1hr highway cruise at 55 mph with an eye on batt vitals, share test findings 🤔
15.6v equalization charge in AGM mode: ouch!
Repeat the secret menu procedure before driving to keep an eye on the grumblings. You will see what goes on with your car after it completes its charge cycle ... go for an 1hr highway cruise at 55 mph with an eye on batt vitals, share test findings 🤔
15.6v equalization charge in AGM mode: ouch!
Last edited by CaliBenzDriver; 04-25-2021 at 02:48 AM.
#37
MBWorld Fanatic!
Thread Starter
yeah, i plan on it next time I take the car out solo (my wife would freak if I was nerding out like this while driving with her in the car, hah hah).
btw, I'm charging the battery using the jumpstart terminals, that should be fine, right?
btw, I'm charging the battery using the jumpstart terminals, that should be fine, right?
#38
MBWorld Fanatic!
Thread Starter
and yeah, totally plan on getting into that vehicle data voltage/current display next time I go out for a solo drive. if I did it when my wife was in the car, she'd be freeking about me driving while nerding
#39
MBWorld Fanatic!
Thread Starter
I'd measured the voltage with my meter a couple hours ago, when I just now did the Vehicle Data thing, I didn't bother with the meter. I figured 'booting up the car' in mode 1 was sucking as much power as my charger could deliver, so any voltage readings were meaningless.
#40
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
wife don't mind geeking while in control !?!🤗
#41
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
DC is not rocket science 🙂
And now you have seen the discrepancy I mentioned in my #26 post. There's half a volt at least between the fluke at the terminals and the display.
post#26 being:
You'll be seeing bucked-down voltage at an accessory like that vs directly at the battery terminals. A possible discrepancy of even a volt. So not sure how helpful that would be. Check it out for yourself with your meter.
And on that note, the hidden menu voltage value behaves the same. Will have to factor that into your analysis.
post#26 being:
You'll be seeing bucked-down voltage at an accessory like that vs directly at the battery terminals. A possible discrepancy of even a volt. So not sure how helpful that would be. Check it out for yourself with your meter.
And on that note, the hidden menu voltage value behaves the same. Will have to factor that into your analysis.
Plugging a voltage monitor in the cig lighter outlet show some voltage drop based on heavy consumers load (A/C, Defrost, Seats, headlts..).
Voltage is lost through the prefuse box Front-Sam and undersized wiring - It's part of the overall low-ball philosophy.
#42
MBWorld Fanatic!
Join Date: Apr 2019
Location: Silicon Valley
Posts: 5,928
Received 3,651 Likes
on
2,428 Posts
MY'14 W212 M276 3.5NA @60kMi
LOL 🤔
Lol you strangely contradict your own argument against me almost every time... I'll take a wild guess that English isn't your first language? Anyway, it's all good You seem to know your stuff.
You don't have to believe me if you don't want to, that's totally fine. But if you go out to your car (any car, this is not specific to mb) and test my claim you'll change your mind.
There will be a negative discrepancy between any OBD II reading and the terminals.
You don't have to believe me if you don't want to, that's totally fine. But if you go out to your car (any car, this is not specific to mb) and test my claim you'll change your mind.
There will be a negative discrepancy between any OBD II reading and the terminals.
There is zero wiring error in the Volt, Amp, (Temp) measurements... the display is trust worthy as it shows precise data.
sensor feeds the display data
No need to complicate the basics with fuzy feelings. The complexity lays in the number of factors involved with voltage management (read pdf doc!!) ✌️
Last edited by CaliBenzDriver; 04-25-2021 at 05:15 AM.
#43
MBWorld Fanatic!
You guys are in deep with this stuff.
For me, does the car start? Yes? Any weird electronic glitches or consumers not working? No? OK we're good.
The car has a way of showing (without the secret menus) when the battery is going. 4-5 years or so is perfectly acceptable.
For me, does the car start? Yes? Any weird electronic glitches or consumers not working? No? OK we're good.
The car has a way of showing (without the secret menus) when the battery is going. 4-5 years or so is perfectly acceptable.
The following 2 users liked this post by LILBENZ230:
DFWdude (04-25-2021),
pierrejoliat (04-25-2021)
#44
MBWorld Fanatic!
Join Date: May 2012
Location: Pepper Pike Ohio
Posts: 1,983
Received 1,158 Likes
on
773 Posts
12 E350 4Matic 13 E350 4Matic AMG Sport
Well, honestly I've always been irked they sacrificed battery life for a half a mile per gallon, or whatever it is, I think they tried to improve this as model years went on, I have a '12 which I believe was the first year of "Blue Efficiency" I always assumed my '13 was much different but after BMW's posting of both charging cycles, seems they only tweaked it a tiny bit from '12 to '13. I also got much longer battery life in older Benz's.
#45
MBWorld Fanatic!
Join Date: Apr 2006
Location: Dallas-Ft.Worth,TX
Posts: 4,651
Received 1,755 Likes
on
1,125 Posts
2016 E350 Sport
You guys are in deep with this stuff.
For me, does the car start? Yes? Any weird electronic glitches or consumers not working? No? OK we're good.
The car has a way of showing (without the secret menus) when the battery is going. 4-5 years or so is perfectly acceptable.
For me, does the car start? Yes? Any weird electronic glitches or consumers not working? No? OK we're good.
The car has a way of showing (without the secret menus) when the battery is going. 4-5 years or so is perfectly acceptable.
The following users liked this post:
Senecan (04-25-2021)
#46
MBWorld Fanatic!
Thread Starter
FYI, voltage drop in wiring is purely a function of Ohm's Law, volts = amps * ohms. If a piece of wire is 0.1 ohm, and you pull 10 amps through it, you will drop one volt. If there is 0 current, the resistance hardly matters, you will see the source voltage.
The following 2 users liked this post by Left Coast Geek:
CaliBenzDriver (04-25-2021),
pierrejoliat (04-25-2021)
#47
MBWorld Fanatic!
Join Date: May 2018
Location: Jakarta-Indonesia
Posts: 4,480
Received 4,553 Likes
on
2,666 Posts
2014 - W212.065 - E400 ( M276.820, 3 liter Turbo) RWD not Hybrid
The following 2 users liked this post by S-Prihadi:
CaliBenzDriver (04-25-2021),
juanmor40 (05-27-2021)
#48
MBWorld Fanatic!
Join Date: May 2018
Location: Jakarta-Indonesia
Posts: 4,480
Received 4,553 Likes
on
2,666 Posts
2014 - W212.065 - E400 ( M276.820, 3 liter Turbo) RWD not Hybrid
If you want to see W212 Facelift charging algo in action, use my data log and do the excel graph. Find attached.
Take note : I disabled ECO mode all the time.
Summary is this :
AA. My W212, will never charge to 100% its battery, I would say 80% and you are already lucky.
BB. It all depends on your "luck" and duration of engine running and how car is driven. The luck portion is rather tricky, because the algo can not predict when you will stop the engine.
So when algo is doing its discharging and then there then you arrive at home and stop engine and keep car for many days = that is your bad luck and you can read 12.4x volts the next day
at battery terminal. If you are lucky, when you reach home the algo so happened to be at charge recovery mode during engine kill.. good for you and next day you can see 12.6x volts at battery terminal.
I have analyze many logging sessions of my drive pertaining to "NET charging", I come to a simple conclusion.
Top up my battery at least once a week, if not twice.... with my 5 amps Ctek charger.
Top up my battery after every car washing, coz opening doors too long even with cabin lights off still wake up the car other electronics and suck battery power.
To know more, you need to log voltage with something like a Torque Apps + OBD2 and get 2 data points per second easy.
There you can see in real time when you do the graph, while driving 12.6 to 12.7 volt is like no charging happening to your battery.
12.5V and below car is discharging your battery.
12.7 up, your car is getting positive charging.
Just to be clear, the instrument cluster amperage reading is what goes IN/OUT to/from the battery as NET and is not representing the alternator GROSS output.
Happy analyzing ..........
Take note : I disabled ECO mode all the time.
Summary is this :
AA. My W212, will never charge to 100% its battery, I would say 80% and you are already lucky.
BB. It all depends on your "luck" and duration of engine running and how car is driven. The luck portion is rather tricky, because the algo can not predict when you will stop the engine.
So when algo is doing its discharging and then there then you arrive at home and stop engine and keep car for many days = that is your bad luck and you can read 12.4x volts the next day
at battery terminal. If you are lucky, when you reach home the algo so happened to be at charge recovery mode during engine kill.. good for you and next day you can see 12.6x volts at battery terminal.
I have analyze many logging sessions of my drive pertaining to "NET charging", I come to a simple conclusion.
Top up my battery at least once a week, if not twice.... with my 5 amps Ctek charger.
Top up my battery after every car washing, coz opening doors too long even with cabin lights off still wake up the car other electronics and suck battery power.
To know more, you need to log voltage with something like a Torque Apps + OBD2 and get 2 data points per second easy.
There you can see in real time when you do the graph, while driving 12.6 to 12.7 volt is like no charging happening to your battery.
12.5V and below car is discharging your battery.
12.7 up, your car is getting positive charging.
Just to be clear, the instrument cluster amperage reading is what goes IN/OUT to/from the battery as NET and is not representing the alternator GROSS output.
Happy analyzing ..........
Last edited by S-Prihadi; 05-13-2023 at 05:26 AM.
The following 3 users liked this post by S-Prihadi:
#49
MBWorld Fanatic!
If you want to see W212 Facelift charging algo in action, use my data log and do the excel graph. Find attached.
Take note : I disabled ECO mode all the time.
Summary is this :
AA. My W212, will never charge to 100% its battery, I would say 80% and you are already lucky.
BB. It all depends on your "luck" and duration of engine running and how car is driven. The luck portion is rather tricky, because the algo can not predict when you will stop the engine.
So when algo is doing its discharging and then there then you arrive at home and stop engine and keep car for many days = that is your bad luck and you can read 12.4x volts the next day
at battery terminal. If you are lucky, when you reach home the algo so happened to be at charge recovery mode during engine kill.. good for you and next day you can see 12.6x volts at battery terminal.
I have analyze many logging sessions of my drive pertaining to "NET charging", I come to a simple conclusion.
Top up my battery at least once a week, if not twice.... with my 5 amps Ctek charger.
Top up my battery after every car washing, coz opening doors too long even with cabin lights off still wake up the car other electronics and suck battery power.
To know more, you need to log voltage with something like a Torque Apps + OBD2 and get 2 data points per second easy.
There you can see in real time when you do the graph, while driving 12.6 to 12.7 volt is like no charging happening to your battery.
12.5V and below car is discharging your battery.
12.7 up, your car is getting positive charging.
Just to be clear, the instrument cluster amperage reading is what goes IN/OUT to/from the battery as NET and is not representing the alternator GROSS output.
Happy analyzing ..........
Take note : I disabled ECO mode all the time.
Summary is this :
AA. My W212, will never charge to 100% its battery, I would say 80% and you are already lucky.
BB. It all depends on your "luck" and duration of engine running and how car is driven. The luck portion is rather tricky, because the algo can not predict when you will stop the engine.
So when algo is doing its discharging and then there then you arrive at home and stop engine and keep car for many days = that is your bad luck and you can read 12.4x volts the next day
at battery terminal. If you are lucky, when you reach home the algo so happened to be at charge recovery mode during engine kill.. good for you and next day you can see 12.6x volts at battery terminal.
I have analyze many logging sessions of my drive pertaining to "NET charging", I come to a simple conclusion.
Top up my battery at least once a week, if not twice.... with my 5 amps Ctek charger.
Top up my battery after every car washing, coz opening doors too long even with cabin lights off still wake up the car other electronics and suck battery power.
To know more, you need to log voltage with something like a Torque Apps + OBD2 and get 2 data points per second easy.
There you can see in real time when you do the graph, while driving 12.6 to 12.7 volt is like no charging happening to your battery.
12.5V and below car is discharging your battery.
12.7 up, your car is getting positive charging.
Just to be clear, the instrument cluster amperage reading is what goes IN/OUT to/from the battery as NET and is not representing the alternator GROSS output.
Happy analyzing ..........
If you never had starting issues and you are doing all this then you are doing it just as your hobby and it is really not needed.
I have not tested my S550 but if I leave doors open on my E550 the car kills power for all internal lights etc. in around 7 minutes.
This all is very interesting talk as a car should not need any battery maintenance charging if the car is used just a couple times a week. I have my E550 sitting now as my daily driver is the S550. I start/drive the sitter every three weeks or so. Between the drives it is not started. Have not had one problem starting it up yet and this has been going on for a year now.
#50
MBWorld Fanatic!
Well, honestly I've always been irked they sacrificed battery life for a half a mile per gallon, or whatever it is, I think they tried to improve this as model years went on, I have a '12 which I believe was the first year of "Blue Efficiency" I always assumed my '13 was much different but after BMW's posting of both charging cycles, seems they only tweaked it a tiny bit from '12 to '13. I also got much longer battery life in older Benz's.
This body style E-class was made for European market already in 2009 and I believe it was in use already then. It may not have been marketed as “Blue Efficiency” before 2012 but I think it has been in cars before that, at least it is in my car.