Best way to charge car battery?
#26
MBWorld Fanatic!
I can tell you that when I have not had the car on a trickle charger and not driven for a few weeks my ECO S/S light will generally not illuminate until I have driven for a pretty long distance. On the other hand if I have had the car sitting on the trickle charger for a day or two and head out, the ECO is illuminated and goes green within the first couple miles of driving.
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pierrejoliat (03-04-2021)
#27
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'11 E350, '11 E550, '98 M3, '95 E320
I can tell you that when I have not had the car on a trickle charger and not driven for a few weeks my ECO S/S light will generally not illuminate until I have driven for a pretty long distance. On the other hand if I have had the car sitting on the trickle charger for a day or two and head out, the ECO is illuminated and goes green within the first couple miles of driving.
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pierrejoliat (03-04-2021)
#28
Member
The Aux battery will not charge until the Power Relay tells it to charge, so using a trickle charger on the main won't keep your Aux battery charged.
The Power Relay looks at main battery voltage and aux battery voltage and has a timer that kicks in after about 15-20 minutes of driving, if the voltages meet requirements. That is what connects the Aux battery to the main battery for charging. So, if you don't drive the car, the aux battery will eventually go dead. Only way around that is to specifically charge the Aux battery itself.
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The Power Relay looks at main battery voltage and aux battery voltage and has a timer that kicks in after about 15-20 minutes of driving, if the voltages meet requirements. That is what connects the Aux battery to the main battery for charging. So, if you don't drive the car, the aux battery will eventually go dead. Only way around that is to specifically charge the Aux battery itself.
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Last edited by Alandf; 03-04-2021 at 11:57 PM. Reason: spelling
#29
MBWorld Fanatic!
install a pair of battery tenders, a junior for the aux battery, and a regular size one for the engine battery, and wire them to a single power cord, so you can just plug the car in when its parked in the garage for awhile.
new world problems.
new world problems.
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Alandf (03-05-2021)
#30
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Does the W213 still have two separate batteries or did MB go to one battery like every other manufacturer?
edit: I guess the answer is no. There is a voltage converter now in place of the trunk battery.
edit: I guess the answer is no. There is a voltage converter now in place of the trunk battery.
Last edited by KEY08; 03-05-2021 at 10:43 AM.
#31
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2016 E350 Sport
...and, how do you charge a "Voltage Converter?" LOL
#32
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I think it's like a capacitor. Once again, this is just the aux batt not the main battery