Original battery

Car has been having issues starting lately. It's my 2012 E550 4matic. I'm guessing this is the original battery since it's a Varta and made in Germany and I doubt replacements are shipped across the Atlantic.
Car won't start, but I put my jump pack on and it fires right up without taking juice from the pack. After 6 jumps my pack still shows 100% and isn't to the 75% level yet.
Leaning toward a new battery but since I only drive a mile and a half to work it may not be getting a good recharge cycle. I've got it on a charger to see if it improves.








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For a cheap battery charger, there's the Schumacher SC3 8amp battery charger, around $30 on Amazon.




They last less and less each year.
Few years back Kirkland batteries had 100 months pro-rated warranty. Not anymore and most common you can buy is 36 months replacement.
Than Jay Leno is still washing 100 years old battery on his fire truck.

I spent Thursday changing the front and rear breaks on this car which I'll post some pics of in a new thread. I noticed something odd while working on it with the hood open. I had the cabin airbox off and I could see the climate control fan running. This stopped as soon as I opened the passenger door. The car had been off for at least an hour. Between Wednesday night and Thursday afternoon I only moved it in an out of my garage to give myself more space on the one side of it while changing the brakes. Is it normal for the interior fan to run while the car is off? I wonder if there is something creating drain. Before I had issues with it starting, my parking sensors, and other systems were giving me errors, which seemed to go away with a good charge.
I almost took the car in because the AC wasn't cooling as well as it should, but decided to wait since I the weather is getting cooler. I hear what sounds like air occasionally hissing from behind the dash, possible AC coolant or a vacuum leak? Are these issues related? Is it time for a new S-class?
At any rate I've got first world problems here.
I spent Thursday changing the front and rear breaks on this car which I'll post some pics of in a new thread. I noticed something odd while working on it with the hood open. I had the cabin airbox off and I could see the climate control fan running. This stopped as soon as I opened the passenger door. The car had been off for at least an hour. Between Wednesday night and Thursday afternoon I only moved it in an out of my garage to give myself more space on the one side of it while changing the brakes. Is it normal for the interior fan to run while the car is off? I wonder if there is something creating drain. Before I had issues with it starting, my parking sensors, and other systems were giving me errors, which seemed to go away with a good charge.
I almost took the car in because the AC wasn't cooling as well as it should, but decided to wait since I the weather is getting cooler. I hear what sounds like air occasionally hissing from behind the dash, possible AC coolant or a vacuum leak? Are these issues related? Is it time for a new S-class?
At any rate I've got first world problems here.
Opening the door will cause it to stop. I do not know what the actual programmed run time is, but I have had it come on, then turn off, then come on again. whatever....
The only hissing noises I have heard was my old 2010 with airmatic letting go of some air. pssssshhhh noise, or a brief popping fart noise.
These cars are noisy!




When we don't have good description how drying program works, it has to be only few minutes and the only way for cabin blower to run for max 1/2 hr is use REST program.
From forum replies I notice that lot of those cars might have problems with door switches.
The car should go to sleep 20 seconds after closing the door. Other members report their Bluetooth still working after 1 hr, what indicate the car did not go to sleep till battery saver clicked in.

I'm not sure if either car is going to sleep properly or not. I've wondered if I keep my keys to close and they "activate" it. My key fobs don't last but few months in fact last time I changed them all 4 keys I got the replace battery within 2 weeks in both cars; which could have been bad batteries. I haven't changed them and its been a month. I frequently get a key not detected message when I try to start the E550 often after I've just unlocked the doors.
I think the two 212's keep each other up talking to each other in German.
Last edited by rediesel; Oct 20, 2017 at 04:25 PM.








Battery use is whole science for those like boodocking in RV, so thank the manufacturer that in car it is all automatic. First batteries hate to be discharged below 50% of its capacity. Not happening in car unless there is failure.
Than battery needs to be "topped off" for long life, meaning low current charging for long time. Most of the time cars are driven on significant distance, so unless you have 1 mile commute, you don't need to worry about it.
Than battery has a number of charge/discharge cycles, but that goes in thousands, so unless you start your car 100 times a day - you don't have to worry about it.
Modern cars have more gadgets to run, but then modern electronics are more battery-saving.
We had 1999-2000 MB models sitting for 5 weeks with alarm on and they started on their own power.
I read on W211 section that lot of those cars stay awaken for strange reasons and that is definitely what can kill the battery.
So from time to time, close your car and stay for 20 seconds observing if all the lights and displays go off. If not- start checking.
and found this out as Varta batteries are now made in the USA by Johnson Controls.and marked as so. Battery life recently is horrible and Johnson makes most of them.
Had a new one in my Suburban in January and it was dead in August, made by Johnson. Just a fair warning!.

and found this out as Varta batteries are now made in the USA by Johnson Controls.and marked as so. Battery life recently is horrible and Johnson makes most of them.
Had a new one in my Suburban in January and it was dead in August, made by Johnson. Just a fair warning!.
Battery life has been bad lately because most newer cars have new charging algorithms that don't fully charge the battery so they can get slightly better gas mileage on their CAFE ratings. I recommend getting a battery charger that's under 10 amps and giving the battery a good charge once in a while as a fully charged battery will last longer than one that isn't fully charged up all the time.





Lately I fired up my ScanGauge on 2014 diesel for DPF monitoring and as side gauge I display car voltage.
The car has variable charging programs, but main point is that in the morning, on car who was driven day before, warm weather, so no electrical load - the car still takes over 6 miles of charging at 14.5V before computer switches to 13.7V maintaining voltage. My diesel fires up in 1/2 second, so the battery is never much discharged.


