newyorker

Hello,

I just bought the trickle charger from Mercedes dealer.

Since the consumer battery is in the back, can't located it, one of the tech told me that I can connect the positive clamp to the tall positive in the distribution box right beside starter battery in the engine room.
Of course black clamp to the groud. I just did that and it seem working but the charger is getting really hot. no fire or melting but it's hot.

Please give me advise if I did wrong...

or any other choices?

I am leaving tommorow for long trip.

Diesel Benz

The correct point for the rear battery is the tall pin on the right in the attached photo.

Are you sure your car was "sleeping well" when you tried the trickle charger? I guess you would have to have the bonnet closed too, I'm not sure how the alarm would behave otherwise and in any case it takes some time for the car before the current drain drops (5 to 15 minutes).

newyorker

Thanks for the info,,,,

I asked tech in the two different mercedes dealer here in NY, Both told me same answer as you. I connected red clamp to the tall pin on the right in the picture and black to the ground. First few hours, it was charging then now it is maintance charging mode. The charger is not as hot as charging mode.
I guess the charger is working very hard at the first time to full charge then just maintain the batter after that.

Anyway, Thanks again for the info,,,,Acutally I saw your post in other MB site but one of the member put his red clamp to wrong on and posted picture, so I was confused....

OH~ the alarm worked with hood open. I can't close it. it will damage the electirc line.. and the manual say keep it open.
Anyway, I parked in my garage in my house, so it's safe.

04S430

Had the same question as Newyorker. ( I don't use my car often during winter months.) Thank you Diesel Benz!

Diesel Benz

Seems you have PM disabled, I'll say thanks to you here! I quite often get frustrating "feedback", probably for a good reason when I lose a bit my temper on a matter that should just be ignored instead of trying to protect my view. But if one out of a hundred posts helps someone else at the forum, it gives the strength to attempt another 99. If someone replies with a spontaneous "thanks", one can easily survive 999 attempts to help without success.

04S430

Happy I made your day!

PHCMA

If it is going to sit in the winter why not just pull the neg battery lead off. The thought that you should start it every now and then makes no sense.

JosanK

There is a new charger out from CTEK (who, I believe, OEM's the Mercedes charger) called the US25000 that can deliver, safely, up to 25 amps to an in place battery. Check out this URL...

http://www.battery-rechargeable-char...ulti-us-25000/

The question is would there be any downside to using this charger on a 2007 S550? Perhaps a fuse issue in the path from the front pin to the battery?

Comments?

Diesel Benz

Is this a new CTEK model? I've had it for a couple of years now. Perhaps it is the US model that is new?

Anyway, this is what I use for charging the car when I want to play with the diagnosis tools on it (on the 221, 212 and the 204, plus visiting cars).

The pole at the engine bay can handle much higher currents than 25 A. But if the purpose is to use the charger as a maintenance charger when the car is parked for a long time, I cannot see any benefits from a 25 A model over the small 4 to 7 A model from CTEK. The big one would just consume some power because of the fan inside of it running.

JosanK

Thanks for the info. I think that the 25000 is fairly new in the US.

Because of construction I have limited garage time. My goal is to "top off" the charge within a couple of hours every week. Also have similar issues for my SL55 and my wife's Acura (they all drain pretty fast). We both travel a lot so the dead battery issue has escalated.

I rigged up a female socket on the 2003 SL55 some years ago (cigarette lighter style). There is a 7 amp fuse in the path that I'll have to remove/enhance to handle the amps from this charger. The wires for this type of plug may not be able to handle 25 amps. May have to redo this.