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ok louis, replaced everything and now down to .7v on charging circuit. So whatever i am doing is effecting only that 12v rail. I pulled the isl off another board. It had no visible damage around it.
So I have replaced it three times now. Two new ones and the last one used. I checked the ISL from the sides to see pin connections and it looked good.
OK, so i figured out that the common denominator was the ISL. So I changed it once again and actually soldered it correctly. Fourth time is the charm.. I now have 12.56 v!!!!!! However, I still can not short power pads for fan spin and charger does not go orange with battery plugged in. I am attaching a photo of the final ISL solder job. I realized that I had heat way too high and I was not getting it just right on the pads.
Resistor measures good, pin 1 on U7840 is 3.4v, SMC_RESET_L is 3.4v on pin 13 of U7000. I have no visible signs of damage around the U7200 but would you recommend replacing U7200 anyway? Is there some way to test if it is good?
Q7221 is related to a different rail. If SMC_PM_G2_EN is not fluctuating, but PP5V_S5 is fluctuating, it's a safe bet your issue is either with U7200(likely) or U7840(less likely, but still possible). You have green light to replace U7200! Bonus points if you don't burn the fan or speaker connector.
Ok, screwed that up. SMC_PM_G2_EN in diode mode measures .023v not fluctuating, PP5V_S5_LDO is fluctuating at .361-.4v in diode mode so it looks like they are shorted to ground.
When I check these points on a working board in diode mode i get OL
1) 0.36 to 0.4v in diode mode is not shorted to ground
2) Please for the love of god tell me you are not making diode mode measurements with power going through the board
3) I asked if SMC_PM_G2_EN voltage is fluctuating. Measure voltage. Is it steady or does it move?