auto start stop system not working

[verymau]

Hi Guys,

I have a 120d from 2009 and I don't believe the battery has ever been changed(bought the car used). Nowadays I only use the car during the weekends and for some months now that from time to time the yellow warning battery light comes on, possibly due to its age and little use. That's fine, I don't mind that, as it recharges when I use the car, but the auto start stop system stopped working. During winter I thought it was because of the cold temperatures, but with summer here, I am beginning to think it is because of the battery possibly not being at its best.

What do you guys think?

Thanks in advance for the help.

Jorge

[Tinsta]

Have you tried putting a trickle charger (like ctek) on it for a few days to get the battery back up to full charge. I did read somewhere that the auto stop/start would disable itself, if the battery charge wasn't quite optimal >80% I believe.