820-3115 sometimes not charging the battery

[Sr. Robot]

Hi, got an 820-3115 with no signs of damage.

The battery usually charges normally but after some time if you disconnect and connect the charger again it wont charge the battery. It powers on the laptop just fine.

Sometimes if you wobble the connector a bit it will start charging the battery, but after a while this doesnt work.

Ive tried different chargers, different batteries, changed the DC in connector, and disconnected J6955. No change.

 

[2informaticos]

Do you get green light on Magsafe connector (when problem appears)?
What is the exact PPBUS_G3H voltage then?

 

[Sr. Robot]

Sometimes the light stays green. Sometimes orange for a while and then turns off. PP3V42_G3H stays at 3.4v

PPBUS_G3H is 12.5v

Replaced U7000 just in case. No change.

 

[2informaticos]

Check continuity between DCIN board and U6900 (ADAPTER_SENSE).
Magsafe light must always be on (green, or amber).

 

[Sr. Robot]

There is continuity between ADAPTER_SENSE and the pin of the DCIN board.

 

[2informaticos]

Then check U6900/1 voltages when this problem happens.
Check trace from U7000 to U6901.

Also reball SMC...