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No boot and no Green light.
One wire has 3.42v at u6900 pins 1,4 and 5
u6900 has 3.42v at pins 1,2,4 and 5.
3.42v at pin 14 u7000 so I have SMC BC ACOK.
No doubt. I'll start over and see what I can find.
I did find a bad R7261 pin side was broken off. weird. I'm not sure if that was an original problem or the result of my shorting out the other resisters.
I measured at those resistors because they were ones that show up when searching for...
PPBUS_G3H "was" stable at 12.6v until I shorted r5301 pin 1 and R5312 pin 1,, now the 12.6v is dropping slowly... no green light any more... $##%!^&#@^....
Previous to my shorting the to resistors.. I had 0v at PP5V_S3.
PP3V3_S5 is pulsing but much less voltage:
r7940 1.002v - .002v
R7812 .998v - .003v
BTW thank you for your help. I'm sure that much of this is a pain in the *ss for you but the assistance you offer is very much appreciated.
This board looked very clean. There was corrosion on J3500 pin 16 but no where else. I used the USC anyway but I couldn't see any other issues.
I'm not sure where to find the course of the PP5V_S0 but after looking and looking It seems to come from U9500.
There is no 5v coming from here.
No...
and yes, I lost the green light sooooo... I somehow blew the U7000 or something else blew it.
learning these circuits is such a pain in the arse but the good side of this is that this is how we learn to understand the circuitry in a very comprehensive way. :)
Badly soldered or a bad U7000. My soldering may not be a work of art but I have checked each solder point for a secure solder and pressed down firmly on the chip as I was placing it (as Louis suggested in a video) so,... Either the U7000 is bad (this last one a used one) or my solder work sucks...
Replace Q7080. I now have 5v that drops to 1.2v on Q7080, Replaced U7000 3rd time with one from another board. The new ones i have been using dont seem to make a difference.
Now I am back to having low voltage on pin 3 of U7000.
R7005 16.2v
R7051 1.2
R7052 1.3
R7021 1.2v
R7022 1.4v
R7010...