00840 20V 0A PPBUS 13.1V

2informaticos

Administrator
Staff member
You've forgot to specify exact PPBUS_G3H voltage (without battery).

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L, at same time.
 

grmacs

Member
PM_BATLOW was stuck low. Checked and near 0 in diode mode red to ground. When I pulled off shield on U2800 a bunch of caps and diodes moved near DCIN ports. I put everything back pulling parts from different board and thought everything was good. Plugged in and board started to try to start and pulling amperage but U2800 fried a hole near the center and dead short on PP3V3_TBT_X_S0. Don't know if it having heat to it finished it off or something else wrong. Not seeing anything out of sorts near the ports. short is gone after pulling U2800
 
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grmacs

Member
Very much appreciate that tip. I wouldn't have guessed it would boot without U2800 considering how Apple is tying everything together before booting. Yes it does in fact boot without the U2800. SO hopefully replacing it will get me back in business. Thanks again!
 
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