Battery tender recommendation SL550
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Joined: Jul 2022
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2007 SL550
Battery tender recommendation SL550
New Mercedes owner here !! I just bought a 2007 SL 550 and do not drive it much. I know it has 2 batteries in it and will probably need to put a trickle charger on it as it won't get driven but once every couple of weeks. The question is what trickle charger is recommended for this car? Do I need to just keep the main battery charged or both? Does it need to be hooked directly to the battery or thru a cigarette lighter? Sorry for all the questions, but never owned a Mercedes and it came with no manuals! Thanks in advance and sorry again if this is in the wrong area of the forum!
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Benz battery float
At the end of the day... buy a CTEK float charger or similar favorite for your MAIN system battery.
Disconnect the AUX to prevent discharge and float once a while.
Disconnect the AUX to prevent discharge and float once a while.
MBWorld Fanatic!
Joined: May 2018
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From: Long Island, NY
2019 E 450, 2016 E350 4matic (retired), 2018 Ford Edge Sport, 2008 Porsche Boxster
I agree that a CTEK charger is an excellent one. They make the chargers branded for Porsche and Mercedes Benz.
On my Boxster, 2008 I was able to keep the trickle charger through the cigarette lighter - it was always live and I used the Porsche branded CTEK. However on my 2019 E450 the cigarette lighter after the ignition is turned off goes dead so to put a trickle charger on you must connect to the main battery terminals, which are under the hood.
Hope that this helps.
Last edited by JTK44; Jul 13, 2022 at 04:59 PM.
