W211 Battery charging ???

[MichaelJohnson]

Good Morning.
My problemis that I have not used my E320 CDI 2004 for some while and need to charge the battery. Please can anybody advise as to any likely problems, should I disconect Positive & Negative leads first and loose my memories, or as I have a Ring Smart Charger where I can select 2,4,8, to 16 amp charge, if I selected 2 amp do I need to disconnect the battery first ?
I would appreciate if someone out there could spare the time to advise me.
Happy New Year to all at our superb Forum.
Regards.
Mike.

 

[Diesel Benz]

If you ask me (you really should not ), put the charger to 4 or 8 amps and let it charge the battery. I've used my CTEK 25A big brother in my car, it is a lot less than the alternator would do anyway. I might use connectors from the engine bay (to avoid spikes at the battery if there are some fumes after charging and when removing the charger, just in case) but it isn't easy to find a plus pole from the engine bay.

 

[Bayram]

Best thing to do would be disconnecting negative lead. Check for battery acid/water. Refill if necessary. Leave the plugs off and let it charge over night at 4-8 amps. Leave the trunk open aswell so the gasses from the battery can resolve easilier.
When connecting negative lead on again, blow it over with a airhose just to make sure theres no gasses surrounding the battery that might cause a little puuf

Might seem a little overkill - but safety first. And by this way you will get the best result.

 

[MichaelJohnson]

Many thanks for your prompt reply, will give it a go.
Regards
Mike

 

[Diesel Benz]

Best thing to do would be disconnecting negative lead. Check for battery acid/water. Refill if necessary. Leave the plugs off and let it charge over night at 4-8 amps. Leave the trunk open aswell so the gasses from the battery can resolve easilier.
When connecting negative lead on again, blow it over with a airhose just to make sure theres no gasses surrounding the battery that might cause a little puuf

Might seem a little overkill - but safety first. And by this way you will get the best result.

But if the battery is an original AGM (VRLA) battery, it would be pretty dangerous to start refilling it.

Disconnecting the battery creates some additional nuisance, if you do it the wrong way, you kill the rear SAM which means a lot of money.