820-4924 wont boot with battery

[rlowe215]

Hello
Im working on a 820-4924 with no sign of damage. Looking really clean and have never been opened before.

It works normal and no problems with the battery disconnected. But if I connect the battery it freeze in the beginning of booting. And PSU shows 3.34 amps constant. Tested with working logicboard and no problems found so something wrong with logicboard. And battery are charged so should not drar 3.34 amps.

Never had this problem before so looking for help where to start.

 

[2informaticos]

Post exact PPBUS_G3H voltage; w/ and w/o battery.
Also post CHGR_A/BMON values.
See what happens starting in SMC bypass mode.

 

[rlowe215]

PPBUS_G3H with 12,17v and 12.6v without
CHGR_ AMON 1,37v
CHGR_BMON 0.05V

SMC Bypass no difference

 

[2informaticos]

CHGR_AMON with charger only?
Check exact ohm resistance between pins 27/28 of U7100.
Board stays on with battery alone, if you remove the charger?