Hello,
i am working on a 820-3115 with waterdamage. I actually fixed this one but it came back for the second time now with no green light. I had to run wires around U7000 and as it came back the first time i replaced u7000 and it worked again. Now i replaced U7000 again and that fixed the green light. But now PPBUS is missing (no short). I followed this path and came to Q7085. It has 16,2-16,8V at pin 1-3 (pulsing up and down) and only aroung 7-9V at pin 5. I guess it has to do with the pulsing voltage. I checked Q7085 and when plugged in it beeps (pin 1 to pin 5) At pin 2 of R7021 i can only measure 4,7V. I checked current sensing already but the resistances are fine (3Ohm and 23Ohm). Now i don´t know where to search next and what to do to prevent it from coming back...
Thanks for any help
i am working on a 820-3115 with waterdamage. I actually fixed this one but it came back for the second time now with no green light. I had to run wires around U7000 and as it came back the first time i replaced u7000 and it worked again. Now i replaced U7000 again and that fixed the green light. But now PPBUS is missing (no short). I followed this path and came to Q7085. It has 16,2-16,8V at pin 1-3 (pulsing up and down) and only aroung 7-9V at pin 5. I guess it has to do with the pulsing voltage. I checked Q7085 and when plugged in it beeps (pin 1 to pin 5) At pin 2 of R7021 i can only measure 4,7V. I checked current sensing already but the resistances are fine (3Ohm and 23Ohm). Now i don´t know where to search next and what to do to prevent it from coming back...
Thanks for any help