Hi Folks,

Thought I would share my ongoing journey with the infamous stop - start system fitted to my Focus.

After reading several posts about possible battery issues with the factory fitted Varta batteries I decided to change my battery.

I purchased a Halfords EFB battery and fitted this to my car, I then used Forscan to reset the BMS system.

On the first journey after leaving the car over night to relearn the battery state of charge, start stop worked after a short distance.

Several other members have indicated that after a few days the start stop would again not work due to low state of charge.

In my case after a month, stop start is still working, the only other thing I did was increase the target battery charge target to 90% using Forscan, however this was prior to the battery replacement.

Previously this target increase also fixed my locking issues and car going into deep sleep mode and many low voltage DTC`s on the car.

I had the original battery tested prior to this and it was fine, according to the garage, 100% health and a good CCA level, with a state of charge above the required level for stop start to work.

So why was stop start not working, I can't say. All I can say is that by changing the battery and completing a BMS reset, stop start works again.

Prior to this it has never worked, I was back and forward to Ford and they just charged the battery and indicated I was not using the car enough.

This was rubbish, my daily commute to and from work is 50+ miles of various town and main roads.

I do believe that it has something to do with the Varta battery fitted by Ford.

Just my thoughts.

 

Mine never works I go for a 2 hour drive and it still only reads 12.1 volts and the alternator is charging at 14.6 volts 

🙄

Turn it off as a matter of course, every time you use the car, it’s a terrible idea, that can induce premature wear to the engine, as well as the starting system.