820-3437-B Not Charging, Battery detected, works from charger

[2informaticos]

"takes 7-12A from charger with battery connected "
Are you sure about that?
That is very high current.
Are you using original Magsafe 2 charger?
Do you get amber light on Magsafe?

 

[aplas]

Sorry It's 7-12 Watt , yes original magsafe2 cable connected to power supply. Yes amber light present.

 

[2informaticos]

Run corresponding ASD EFI and see if any error pops up...