Auto Stop Start

[DaveG1975]

Does the new Focus have a second battery for the auto stop start to work 

[TomsFocus]

Stop start uses the normal 12v battery.

Some models are now going mild hybrid which uses a second 48v battery.

[iantt]

Standard focus doesn't. Mhev focus has a small 48v lithium battery that is utilised to restart the engine on stop/start . 

 

[DaveG1975]

I have a 2019 diesel focus vignale does that have a second battery?

[iantt]

Nope. Mhev focus not long been produced. 

[Freeze]

If other conditions are met, the reason for your start/stop system not working is probably due to low voltage in your battery. Have your battery recharged with a charger that provides AGM battery mode for charging, with my charger it-s abutton that states "14.7V".

Start-stop system not working properly in the new Focus Is a common problem,  Google it. Has to do with the BCM system.

[Botus]

fitted to sell more cars

use of this feature severely wears the engine, alternator and battery.  It also increases the risk of accidents / our safety at junctions (but again those incidents would sell more cars too).  The environmental damage of using this stupid feature - due to repairs, replacement cars and engines and medical treatment - is probably well over a 1000 times the benefit people think it brings.  

knowledgeable owners have it switched off permanently in software - it is probably the single most wanted thing changed in software across any brand of car worldwide.

one airliner taking off, puts out more pollution than this saves for every car in the UK for the whole year