820-00840-A No boot

[2informaticos]

Change them directly if you have scrap boards.
In fact, I never found bad Q7030/40, but few times I saw Q3100/200 failing.
In your case, Q3100/200 should be good if power ports switch to 20V.

As general rule, Gate pin of MOSFET must show OL (diode mode) with any other pin; measured out of board!
Source-Drain should measure like a diode (silicium).

 

[sourcensolutionsonline@gm]

Ok , Then You suggest that I change Q7030/Q7040 which I did last night both of them just to see if the behaviour would change but the result remained the same I am not too sure if U7000 is my culprit , I was going to simply remove it by a new one to see if I get a boot , let me know if you suggest me to do so .

 

[2informaticos]

I left U7000 as last option, if all previous mentioned components are good.
You should change it, if have known good one.

 

[sourcensolutionsonline@gm]

I have changed Q7030/Q7040 to newer ones but still not ok , but there s something that i found here , I have another known good board that i am comparing the values with , on my know good board PPBUS_G3H resistance value in diode is is 0.287ohms and on the board that i am trying to repair it's 0.408 ohms which I found too high and If I try to look for short using 3v on the DCSP there s no consumption wheresover. Do you suggest that i change directly Q3100/200? I am thinking that they are doing ok since i am getting my 20V

 

[2informaticos]

Don't touch USB-C area, if you get 20V!

How can you suspect a short, when you get higher reading to ground???
BTW, is strange to mention "resistance value" in diode mode; don't write "ohm" after diode mode reading (nor V).
Diode mode readings to ground differ if on that rail is connected a Schottky diode, or not.

You should always compare diode mode readings on PPBUS_G3H power rail in reverse mode too; black probe connected to ground.

Check diode mode to ground at SCL/SDA lines of battery bus.

 

[sourcensolutionsonline@gm]

Ok , I agree , Let me do that , I do not touch the USB-C area at all .

 

[sourcensolutionsonline@gm]

PPBUS-G3H in reverse mode promptly goes to 1.989 then changed to OL , Let me check SCL/SDA lines of battery bus.

 

[sourcensolutionsonline@gm]

SMBUS_BATT_SCL =0.390

SMBUS_BATT_SDA = 0.391

 

[2informaticos]

All values look good.
Try changing U7000.

 

[sourcensolutionsonline@gm]

I have a few here I believed that I got them from Rossmangroupstore , but they are 9239CO but the original one on the board is 9239HI would they work the same?

 

[sourcensolutionsonline@gm]

I have taken my time to check entirely all the power lines of U7000 from a known good board to compare with the one that i am repairing ,this is a very small report of the lines that i found in diode mode too low and some others too high

TBA_GATE Q4 on the good board I have in diode mode 0.750 and on the bad one i am getting 0.719
PPBAT_G3H_CHGR_REG on good board diode mode is 0.273 and on bad board 0.405
TBA_CSOR_P good board = 0.273 and bad board is 0.405
PPVIN_G3H_CHGR Good board =0.449 and bad board is 0.519
TBA_CSOR_N good board is 0.272 and bad board is 0.405
TBA_LX2 good board is 0.337 and bad board is 0.302
TBA_GATE_Q1 good board is 0.751 and bad board is 0.715

I am not sure if that could give us an idea of why some of those lines are high and other ones a little lower , the other lines that i did not mention are all equal values comparing the good board to the bad one.
I hope that it is not a inner layer issue , the customer reported that before the macbook went off completely it was going off then turn back on by itself after the water spilled on it but the board is intact no sign of water on the board at all.
Please help me out .

 

[2informaticos]

Board has been affected for liquid somewhere, for sure.
Change U7000 before continue.

 

[sourcensolutionsonline@gm]

Yes , I did Replace U7000 and the behavior remained the same . I have asked you an idea regarding the original U7000 chip with the marking 9239HI and the one I purchased 9239CO if they make a difference , I have also reballed 3 different U7000 from donor boards and no luck at all, I got the new ones with marking 9239CO let me know if they work the same.

 

[2informaticos]

I don't remember to done such a swap; it should work, I think.

Check PPBUS_G3H and 3V3_G3H with both charger and battery connected.

 

[sourcensolutionsonline@gm]

Ok, I checked PPBUS_G3H voltage with Battery and charger connected and i got = 0.879 , and PP3V3_G3H = 3.373

 

[2informaticos]

Did you connect battery data cable and screw?

 

[sourcensolutionsonline@gm]

Yes correct

 

[2informaticos]

Try reballing SMC...

 

[sourcensolutionsonline@gm]

A very quick update , I think that i got the issue figured out , What I did at last i used my thermal imager to scan anything for short , and i found right next to U2800 right above it which is not even mention on the schematics neither the board view but the Markings on that chip is PI3U5B32 looking like a voltage regulator right beside the back of the magsafe it is so i removed and replaced it and Boom I got a boot , it is now charging pulling 33.8 Watts and 1.78 Amps
Iam keeping an eye on it as during the process i had to replace that chip twice and the second one is the one working now , so i also had to replace U7000 As the 9239CO was not working .

I will keep on monitoring it if anything I will let you know , thank you for now for keeping up with me in everything step of the way , I really appreciate it

.

 

[sourcensolutionsonline@gm]

Sorry for so much of typos , I meant in every step of the way , my apologies .