820-00928 Fans full speed

[No-Clean]

Board came dead with a short on (C3521 PP5V_S4) and no USB data on that same side, after replacing U2800 I now have data, board boots but fans spin at full speed, when checking sensors I get that heatpipe sensor is high temp, already tried a new heatsink and checked the board for knocked components or corrosion but no luck.

Please advice.

 

[2informaticos]

The ALS works correctly?
You can try disconnecting camera flex from T-CON board.
Also test with known good trackpad board/flex.

 

[No-Clean]

I put this board on a different case/screen/battery basically a board swap on another know good case and same thing happens.

 

[2informaticos]

Check if something else appears starting in Diagnostic mode.

 

[No-Clean]

D mode comes up with error code PFM006 SMC problem.

 

[2informaticos]

Temperature sensors are listed on page 54.
Check for broken trace, or knocked off components.

 

[No-Clean]

Thanks a lot, Thermal sensor U5850 had a tiny bit of corrosion, this was closed to where the short was.