W211 battery situation.

[John]

Given the issues that the W211 has with battery power, what do people do who fit large sound systems or other peripherals or what do the regular tuners / servicing indes on here recommend?

Are second batteries and option or is it a case of fitting caps or similar.

Strikes me that the 12v system is right on the limit in these cars (E55 in particular).

 

[V12]

Plug in battery maintainer should be fine. You'll only have issues if doing lots of short trips.

 

[John]

The reason I ask is I had a new batteries in the last couple of years and I got a convenience error (albeit only once since).

Just surprised.

I don't do small trips (18 miles each way to work).

 

[Vilus]

I have a decent battery on mine, yet still get the convenience warning if I don't use it for 2-3 days in the winter. In summer it's fine. If I plug it into a CTEK charger it shows fully charged after a few minutes of charging.

Since I only use the car for trips to Tesco during the week I was advised to leave the Comand switched off during short journeys, as the powering down to sleep mode drains quite a bit. I have been doing this recently and have noticed that I don't get the convenience warning as often.