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If Blue Efficiency means the car has this smart charging system they started it probably in 2009 already. My E550 is a 2010 model made in May 2009 and it has the smart charging.
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.
From a press release from March 2009 upon the announcement of the new E class (W212)... Looks like its aerodynamics, energy management, using the alternator for braking, eco start/stop, and all the economy displays on the dash. and here I thought it was the 'new' direct injection multi-shot/multi-spark M276/M278 engines, silly me.
BlueEFFICIENCY: Energy management and reduction in emissions: package of measures for efficient environmental protection
Aerodynamics: controllable fan shutter behind the radiator
Energy management: on-demand control of the ancillary components
Alternator control: conversion of braking energy
ECOstart/stop function: switches off the idling engine to save fuel
Cockpit display: information for energy-saving driving
BlueEFFICIENCY – the trademark for exceptionally economical and ecofriendly Mercedes passenger cars – is a package of measures compiled by development engineers across all disciplines, the main aims being to reduce weight, aerodynamic drag and rolling resistance, to further optimise the engine technology, and to make energy management even more efficient.
(8 more pages of blahblah)
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.
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 ..........
That's a lot of converging evidence from fair minded contributors.
Without splitting hair over complex details, we can say the need to recharge our battery points to a problem!
These cars don't work well with tired batteries and get really happy with floated batteries... good performance is voltage dependant. That's our incentive to fix this.
Lazy "bluetech" opportunistic charge is a good idea... deep discharge is a dangerous bug. Use the IC display to see what your car does AFTER battery charge cycle (14.9 > 13.5 > 12.6V) is complete... crazy deep discharge below 12v ??
When you look at your IC you'll see that sometimes voltage Mgt respond to a HIGHER LOAD condition with a couple seconds delay... based on reference pdf that is normal.
What is abnormal is to drain high Amps under 11volts at highway speed on a 10KMi car.
Ohm's Law, yeah, that pesky little thing. Now you're just driving me nuts Lol. A 1V drop in a 12V circuit over 5 feet? You'd have to run like, a 60g wire.
Power is being cleaned up and bucked down somewhere for the ECU and other chips is all I was saying. Not a problem, just a factor for your assessment. I'm just gonna blame everything on you from now on LOL
Ohm's relationship between resitance current and voltage is limited to static DC circuits.
In dynamic systems we deal with the IMPEDANCE.
Feeding 20kHz power spikes to piezo injectors, coil over plugs, PWM engine fan, blower, seats heaters involves the dynamic impedance of the power supply.
INCENTIVE:
A well charged battery yields low impedance for a very responsive engine. Tired battery yields slow poke heavy car.
🙂
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.
This all sounds a little nerd-hobby thing to me. It was odd to see a moving E350 say 11.9V on the display. I have watched my display for long drives and never seen below 12.3, and that was with the engine off at a light and at 12.3 the car kicked the engine back on and went to 13.5 or so. Our Macan had this same technology, but it had a dedicated, always on display for the charging system. 12.3 also was as low as it would go during eco engine/off and it never went below 13.1-13.3V while the engine was running at any speed. The last car I had that went below 12v while moving was my 2009 W211 and that immediately prompted a red screen charging error fault warning. Turns out the car had a burned wire somewhere from the tint shop improperly jump starting the car.
I haven't seen mention of this in the W212 operator's manual, but our Macan's manual stated that trickle charging was necessary if the vehicle wasn't driven at least weekly. The OEM battery lasted 6 years, and it was a Varta H8 AGM just like the E. But no aux battery in the Macan.
well, I just took a ~40 mile test drive, at an average speed of 44 MPH, including first 15 or so miles of 2 lane rural roads and some twisty 2-lane mostly level highway, then about 8 miles of 4-lane freeway, then climb to 2000 feet at 55ish MPH then back down, then back on the same mostly level freeway.
nearly the whole time the system voltage per the Vehicle Data display was hovering around 14.5-14.6 V and the current was in the sub +1 amp range. during the few ECO stops, of course, it drops to 12.X V while drawing, eeeeek, 25 amps from the main battery. upon restart it pumps 14.8-14.9V with as many amps as the battery can take (+40 amps at one point) til the current drops back to sub 1 amp and the voltage receeds to 14.5-14.6V again. a FEW times I saw 13.9V or so while driving for a couple seconds, usually around a brisk throttle application but under no conditions with the engine running was it ever 13.6V or lower.
so I dunno, I'm not going to sweat it until we need another battery.
Yep you got it 100%. Our cars are technically similar.
The long list of fancy BlueTech is A-Ok when it works.
Most cars have healthy electricals but many have a birth defect that nukes batteries flat while driving.
(unrelated to drain while parked). This is what I am pointing out.
Healthy cars like yours do not show that class of problem.
When your large AGM needs repeated attention: OP: "LOW BATTERY..." don't just keep recharging or replacing it... instead check out vitals while driving to witness disfunctionsl discharge below 12v.
When a tire keeps getting flat, do you rationalize it's normal to add air -or search for nail ??
I am used to analyzing problems to identify fixes.
🙂
well, I just took a ~40 mile test drive, at an average speed of 44 MPH, including first 15 or so miles of 2 lane rural roads and some twisty 2-lane mostly level highway, then about 8 miles of 4-lane freeway, then climb to 2000 feet at 55ish MPH then back down, then back on the same mostly level freeway.
nearly the whole time the system voltage per the Vehicle Data display was hovering around 14.5-14.6 V and the current was in the sub +1 amp range. during the few ECO stops, of course, it drops to 12.X V while drawing, eeeeek, 25 amps from the main battery. upon restart it pumps 14.8-14.9V with as many amps as the battery can take (+40 amps at one point) til the current drops back to sub 1 amp and the voltage receeds to 14.5-14.6V again. a FEW times I saw 13.9V or so while driving for a couple seconds, usually around a brisk throttle application but under no conditions with the engine running was it ever 13.6V or lower.
so I dunno, I'm not going to sweat it until we need another battery.
Great driving sample!
Your voltage never went below 13.6v
Your car did not exit its "charging cycle" or it would have gone down to 12.6v. The ECU assumed your battery needed to get more charged despite only 1Amp, a sign it was getting near full.
Keep an eye on it to see it exit "charge cycle" and hover normally around 12.6v courtesy of RearSAM management. That will be the most interesting part (without headlight or consumers).
Last edited by CaliBenzDriver; 04-25-2021 at 07:28 PM.
From a press release from March 2009 upon the announcement of the new E class (W212)... Looks like its aerodynamics, energy management, using the alternator for braking, eco start/stop, and all the economy displays on the dash. and here I thought it was the 'new' direct injection multi-shot/multi-spark M276/M278 engines, silly me.
BlueEFFICIENCY: Energy management and reduction in emissions: package of measures for efficient environmental protection
Aerodynamics: controllable fan shutter behind the radiator
Energy management: on-demand control of the ancillary components
Alternator control: conversion of braking energy
ECOstart/stop function: switches off the idling engine to save fuel
Cockpit display: information for energy-saving driving
BlueEFFICIENCY – the trademark for exceptionally economical and ecofriendly Mercedes passenger cars – is a package of measures compiled by development engineers across all disciplines, the main aims being to reduce weight, aerodynamic drag and rolling resistance, to further optimise the engine technology, and to make energy management even more efficient.
(8 more pages of blahblah)
Hmm, Makes you wonder why they waited to be proud enough to put this on the fender in 2012, and I believe took it off again for '13 and I think the '10 and '11 have a different alternator than the '12-'13, go figure...
Last edited by pierrejoliat; 04-25-2021 at 10:13 PM.
Are you having starting problems and this is why you charge your battery every week? Or are you doing it just because you measure the voltage and you want it to be higher?
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.
Nope, no starting issue at all Arrie. However I may not use the car for 7-14 days sometime. I work from home and basically I am 90% retired hahaha.
So usually once a week on Sunday, I take car out to do a 35 - 70 KM run around on the highway.
Yes, keeping doors or boot open, after a while system will turn the lights off, but you still woke up the computers on board and if we do this often battery does get discharged.
As for battery state of charge, best to keep it fully charged. This way the plate sulfation is less and hoping maximum life can be achieved.
The reason I choose only a 5 amps Ctek is because that is a "polite" charger of low power and I can do the once/twice a week top up charge routine in absorbtion to float mode depending on how often I access the car interior.
My W212 is the only car in my garage which can give me 12.4V next day after use, as explained when I get the "unlucky" session of the alternator charging algo when I shut down the engine.
My other cars are still kinda "dumb-down" charging routine by the alternator and 12.7V next day is usually what I get and they do not use much computer power when "waking up" as in door opened etc etc.
Anyhow, I am very **** when it comes to DC/AC electric matters on products I own or manage.
==============================================
Since we are talking about AGM and charging, I might as well share some information for future members who is not much into electrical 101.
Below is for my Varta AGM and I will explain how to read the spec, it for those who may not know :
Charging current in Bulk mode is 25% - 35% of the battery rating. C20 is our automotive battery rating. So for a W212 wih 80Ah, maximum at 35% is 28 amps.
C20 rating for my 80Ah battery meant Varta discharged it at 4 amps for 20 hours till it hit 10.5 volts.
Electric Forklift batteries ( traction) uses C8 discharge rate usually and if a 80Ah battery from a C20 rating used as a C8, it pobably then become a 55Ah or less. Yep.. that is how batteries are rated.
If anyone of you uses a Ctek, more so a 5 amp one like mine, some 101 for you...............
The Ctek at 5 amps is 5/80 = 6.25% charging rate of the 80Ah, that is absortion charge territory.
Absortion charge is the slowest process of charging any battery, more so a sealed lead acid or AGM.
Battery 80% SOC rise 100% (SOC) state of charge falls under absorbtion charge, doing it slow here is good for battery life.
This is the reason I buy no bigger than 5 amps Ctek ( MSX 5.0) , because absorbtion charge is my target, not the bulk charge.
For float charge, I don't do it long hours for the w212. Maximum I allowed the charger to still be hooked to battery after the last final green LED is lit is 2-3 hours max.
I also never use the battery recondition option on the Ctek.
Ctek charger is allright, put poor thermal/cooling design. Its quick clip connector is NOT good.
From User Manual https://www.ctek.com/storage/28170E5...-low-UK-EN.pdf Temperature Compensation : Built in charge voltage compensation according to ambient temperature
I wonder where does Ctek place its temperature sensor , if not inside the casing ? LOL
I hope its first 10 seconds of a Ctek operation is the ambient temperature definition and not any longer duration of sensing.
This also means, let the Ctek cool down to room temperature before using it to charge another battery.
Usually the voltage compensation per 1 Celsius increased in ambient temperature above 25C is (MINUS ) -3 to -5 millivolts depending on battery brand.
Poor quick clip connector design. 5 amps flow and then 13C temperature rise in a short period is NOT good.
After some hours of charging, quick connector gets even hotter, 40C temperature rise at insulation is pure CRAP !! That middle hot spot is where the copper male + female connector inside it meet/interface/clicked.
That reminds me, I got to fix this....
Plastic body, no cooling fan, not even any metal cooling fin sticking out... poor thermal design. 30C temperature rise on plastic body, that means the power semi conductor inside is hotter by 5C - 10C easy. NOT good !!
Below image is Ctek top surface.
Below image is Ctek back side surface. See Sp1 64.6C , do not be fooled, it is not 64.6C, it is lower..........that is due to reflective sticker on that rectangular small area is and its emissity is higher and read as though as hotter.
57.8C is the actual temperature and that is HOT, +27C over ambient temp.
So, in the quest for least error of charging voltage compensation assuming the Ctek thought that my ambient temp is so hot at 50C while actually only at 31C - 34C.... and also to make sure Ctek can last as long as possible, DIY cooling I need to do.
Take a peek on how I placed the quick connector to get maximum cooling blast from the fan crude but it works.
NOTE : I always charge my W212 battery only when it has reached room temperature.
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 ..........
I am combing through your dataset. I have reformatted the columns to help make sense of it.... some deep discharge spotted...
time spent below 12.6 🤔
I can see you went down to 11.8V and kept discharging below 12.6v for a while. Couple pronounced deeps in voltage.
(- I am going to analyse the pattern and transitions to guess what your car was up too... going to catch some rest for now )
Last edited by CaliBenzDriver; 04-26-2021 at 06:26 AM.
Reason: graphs
heh. so when I got in the car to do this test drive today, while trying to push the button sequence, I accidentally redialed the guys we just sold our old Casita fiberglass 'egg' travel trailer to. they were up in oregon camping and having a blast. ooops. i'm sitting there trying to get Vehicle Data and I get a conversation instead. hahahahahahaha.
I think sometimes my wife gets home, and sits in the car for 10-15 minutes and finishes listening to whatever she has on.... if the car is sucking 25 amps that whole time, ouch....
thats probably why I read 12.08V the next day.
Last edited by Left Coast Geek; 04-26-2021 at 05:53 AM.
ok thats weird. that spreadsheet, he spent a LOT of time in the low 13V range over a 30 minute drive.
a few hours later I did the drive I described above, 45 minutes or so of roads with very few stops, both steady speed and winding turn stretches, then a 55-60 MPH 2000 ft climb, and back down again. the voltages were in the 14.5-14.6V range most of the time as I detailed above.
so, huh.
ok, yeah, I had fully charged our battery last night, took the charger off this morning and put it away. before disconnecting the voltage from my Noco to car battery was in the 13.5V range, typical float maintenance voltage
I think sometimes my wife gets home, and sits in the car for 10-15 minutes and finishes listening to whatever she has on.... if the car is sucking 25 amps that whole time, ouch....
thats probably why I read 12.08V the next day.
That little voltage display is really empowering once you start using it.
Train her to do the same routine but idling with driver door opened.
Benz calls this the "Jump Mode". It delivers 14.5V so long the car stays parked - Go try it and have a look at IC, this is a super easy solution for "self-jumping" your battery to a greater level. 👍
You won't need to mess with NOCO charger as much.
Last edited by CaliBenzDriver; 04-26-2021 at 09:26 PM.
Parameters & uncertainty
- I simplified the voltage to 2 decimal digits.
- I use 12.59 volt and lower as DISCHARGING. What amperage discharging, I dont know as I do not have amperage logger.
- I use 12.60 to 12.70 as neutral, no discharging and no charging.
- I use 12.71 and above as Charging. What amperage charging, I do not know.
The common way
The easier seconds counts of 3 different parameters
Attached the working excel fie. I am kinda excel stupid when it comes to making graph , so I did what best I can do.
Hence I summarized, typically my W211 facelift with ECO start stop and whatever firmware version of charging algo I do not know of.............. is giving me 80% battery state of charge most of the time after engine shut down, when and if I am lucky.
80% is not bad though, but I like 100% and I choose to do so manually. In fact for an alternator to do absorbtion charge is not feasible unless I drive a very long journey.
To know discharging is quite easy for my W212. If my HVAC blower speed at 3 or 4 level bars, when car algo doing discharging I can tell by the slight slowing down of the blower.
this is the time spent discharging below 12.3V
discharge time below 12.3v
This is not what it should be like. The very Minimum should be 12.6V or above regardless of Consumers and idle (unless ECO cycle).
Your overall voltage really looks very unstable ie. out of control.
I don't think voltage algorithm has any logic to deep drain the battery. It tries to exit "charge cycle" around 80% target then 12.6v maintenance.
With high Consumers such as A/C... voltage is supposed to be jacked back up above 13x
The graph shows countless charge/discharge/charge spikes. Once AGM's charged, the ECU quits doing the 14.9v regenerative. It goes for steady voltage, no yoyo.
what do you say... about that?
😏
Last edited by CaliBenzDriver; 04-26-2021 at 07:30 AM.
I honestly dont know Cali.
The only thing if I can dig deeper is to get another W212 prefer if an E400 facelift of same year and with same 200A alternator and do a follow me run around for 1 hour and see which car has a dumb-er algo
Next is to actually get a logging amperage meter which can add on its own total charge and discharge and must have time stamp and CSV output with at least 1 sec per data point or better.
Previous to OBD2 logging, I used a camera to record the dashboard/display for 42 minutes, it was my driver driving the car. That was back in April 2019. I can load it up to utube the speed-up version but still a 12 minutes video though, just for the sake of knowledge if any of you want to take a look.
The good thing about the video is, when discharging occurs voltage does not always go below 12.6V, untill algo discharge more or longer because battery is still very full and discharge amount not enough to drop voltage.
So overall the video shows when discharging occurs amperage wise like how if say an amperage logger is available.
We are making great strides towards identifying the cause of LOW voltage swings.
1- The central issue is the broken ability to take in consideration high Consumer loads with a 14.3v output as designed.
2- In addition, the stable voltage regulation at 12.6v is also broken or MIA... (this phase acts as a built-in float charger once the base charge cycle to 80% is complete).
These 2 functions not working is what promotes the low battery charge problem when the uncontrolled voltage falls deep below 12.6v for extended periods at cruising speeds. 🙂
I am not sure yet what is causing that. A Xentry session would really come in handy. reference stages of voltage Mgt.
DESIGN WISE:
Once the ECU is satisfied with the quick charge up to about 80%, it exits the rapid "charge cycle" and switches to 12.6V maintenance. It still charges with opportunistic 14.9V bursts during decelerations up to 100% level then disables the burst logic.
CAN CHARGE UP TO 100% :
I am saying the design does NOT prevent charging above 80% with 14.9V bursts.
When you drive with healights ON (13.5v) or down hill for an extended time... the AGM does end up around 100% (1Amp charge current).
It is false to believe the logic tries to camp at 80%. That's just where "rapid charge cycle" ends.
The voltage control logic does not include the ability to purposely deep discharge. The algorithm is for charging Mgt, not discharging.
FYI... ALT FAILURE:
When the control logic commands a low output to the 180Amp alternator in parallel with 800CCA AGM, it fries a couple of its diodes.
Replace alternator, same thing again! 🤣
Last edited by CaliBenzDriver; 04-27-2021 at 02:54 PM.
Reason: Devil always in the details
Information available in WIS gives us a taste of what's going on... its pretty obvious the goal is to keep the battery "undercharged" and they also hint that voltage can fall below 12.6/12.7 VDC
Originally Posted by bmwpowere36m3
To throw a final complication into things, when the car is in alternator management it can:
Sets a lower voltage in exceptional cases (e.g. stall prevention, cold start at high altitude, catalytic converter heating)
I'll assume thats lower than either the 14.3, 13.5 or 12.6/12.7 depending. Unfortunately really complicated, ideally you'd what to know what the control module is commanding and then verify that output from the alternator. Then continue based on whether is agreeing or not.
Without geeking out... the combination of undercharging scheme, higher consumer demands [amperage] and a year that left many driving less... it isn't surprising battery life may suffer. It was an already common complaint pre-pandemic in cars with smart-charging vs "traditional" charging.
I also have a commute that is short with lots of stop as I'm in the city. I have a two channel Dashcam system that runs with parking mode, so when the car is off, I have it to stop at when the main battery is @ 11.8 volts. I recently purchased an energizer car battery charger from Costco, an 8A one. I let it charge for about 6 hours or so, and it went to 14.4 or 14.6 volts. The next day, the car turned off at the very first light which is about a minute away, and while everything was still cold. However, this didn't last in the following days because of my dash cam I'm assuming. I can't even find my auxiliary battery as it's not in my trunk, or in the front wood trim on either side, nor did I see it in the passenger side footwell where I just replaced the cabin air filter last week lol.
i would set that dash cam to shut off when the battery is below 12.2V or so. 11.8 is deep discharge land for a lead acid.
Having watched my E350 sucking 25 amps at each eco stop, I'm disabling it from now on.
I have no idea where the aux battery is on a CLS400, what year is it ? thats not a W212 anyways, could be a C219, C218, or C257 depending on the year..
i would set that dash cam to shut off when the battery is below 12.2V or so. 11.8 is deep discharge land for a lead acid.
Having watched my E350 sucking 25 amps at each eco stop, I'm disabling it from now on.
I have no idea where the aux battery is on a CLS400, what year is it ? thats not a W212 anyways, could be a C219, C218, or C257 depending on the year..
Yeah, I'm gonna change it back to shutting off at 12 volts like it used to be, don't need 11.8V for extended parking mode as I don't park in public anymore due to corona. It's a 2016 CLS400, so C218. The American CLS400's have their aux battery in the trunk next to the spare tire, not the case for me lol. Perhaps a Canadian E400 owner can chime in.
04-25-2021, 01:44 PM
crude but it works.
