Thanks for your excellent video, very well explained. I have an SL55 in my garage and this happens. I have it on tge trickle charger but sometimes even when there is voltage in the battery it won't charge, it might be the charger though. Strangely sometimes even without the charger mine can be ok for weeks, then other times it goes low after a few days, no pattern to it. Greetings from Northern Ireland.
@@daviddrummond8729 Have you checked the battery itself? How old is the battery? After 7 or 8 years most battery cells become weak so that the power cannot be kept. That would be the first item to check. And please check if you have any auxiliary items. Like Bluetooth phone adapter or any other items. Have you checked the power of the battery with the car shut down? A so called rest power measurement?
@@daviddrummond8729 My Ferrari is always connected to a trickle charger. But this spring I was not able to start the car. The battery was down. The brand was FIAMM. A quality brand. But after some years it is unfortunately necessary the get a new one. Especially the SL has multiple control units which need a small amount of power even if the car is locked and is sleeping.
The trunk battery(auxiliary battery) needs a trickle charger to keep the battery primed. I have an CTEK MXS 5.0 trickle charger on my 2009 SL550 auxiliary battery charged at all times. Whether the car sits for a day or several months, the auxiliary battery is hooked up to the trickle charger.
@@jgonzalesm6 If you ever need to change. please buy yourself the battery. It is made by Varta. Mercedes puts just their own sticker on the battery additionally. The main dealer will charge at least the double price just for that sticker
good Video Doc!
@@kevhauser Thank you very much
Thanks for your excellent video, very well explained. I have an SL55 in my garage and this happens. I have it on tge trickle charger but sometimes even when there is voltage in the battery it won't charge, it might be the charger though. Strangely sometimes even without the charger mine can be ok for weeks, then other times it goes low after a few days, no pattern to it. Greetings from Northern Ireland.
@@daviddrummond8729 Have you checked the battery itself? How old is the battery? After 7 or 8 years most battery cells become weak so that the power cannot be kept. That would be the first item to check. And please check if you have any auxiliary items. Like Bluetooth phone adapter or any other items. Have you checked the power of the battery with the car shut down? A so called rest power measurement?
@@daviddrummond8729 My Ferrari is always connected to a trickle charger. But this spring I was not able to start the car. The battery was down. The brand was FIAMM. A quality brand. But after some years it is unfortunately necessary the get a new one. Especially the SL has multiple control units which need a small amount of power even if the car is locked and is sleeping.
The trunk battery(auxiliary battery) needs a trickle charger to keep the battery primed. I have an CTEK MXS 5.0 trickle charger on my 2009 SL550 auxiliary battery charged at all times. Whether the car sits for a day or several months, the auxiliary battery is hooked up to the trickle charger.
If you use a AGM battery. A charging every 2 weeks is enough
@@dr.p.t.2500 - Yes, I believe it's an AGM battery since it's still the OEM battery from Mercedes Benz.
@@jgonzalesm6The OEM is a Varta silver dynamic AGM 70 Ah. Called A7.
@@dr.p.t.2500 - I see. Both the starter battery and auxiliary battery on my car have the OEM Mercedes Benz logos(stickers) on them.
@@jgonzalesm6 If you ever need to change. please buy yourself the battery. It is made by Varta. Mercedes puts just their own sticker on the battery additionally. The main dealer will charge at least the double price just for that sticker