820-00165 not coming on, green light

[nelo1012]

820-00165 with damage U7100 pin 12 (pp3v42), replaced U7100 and corrected all other burned caps and resistors

also damage around SMC , C5125, L5001, C5001, C5020, REPLACED ALL and also replaced SMC with known working,

there was damaged at U1950, replaced also C1950

There was damage at U1900, Replaced also C1910



PP3V42_G3H 3.42v

PPBUS G3H 1.5v

PPBUS_S5_HS_COMPUTING 1.5v

PPBUS_S5_HS_OTHER_ISNS 1.5v

PP3V42_G3H 3.42v

PPVRTC_G3H 3.39v

PP5V_S5 1.76v

PP5V_S0 0v

PP3V3_S5 0.49v

PP3V3_S4 0v

PP3V3_S3 0V

PP3V3_S0 0V

 

[2informaticos]

"PPBUS G3H 1.5v"
Missing mother of all secondary voltages.
Why continue measuring other voltages then?
Only 3V42 is independent, and present in this case.

Post diode mode to ground at F7140.
If strange value, renove it and see which pin.

Also post exact resistance (ohm scale) between pins 17/18 and 27/28 of U7100.

 

[MOMOH]

2informaticos ?Also post exact resistance (ohm scale) between pins 17/18 and 27/28 of U7100? please tell me , you usually ask for this , what?s the intended? Would low resistance here point to a bad ISL or it?s needed for a different section of the circuit ( am trying to understand, do you usually need the details to confirm the healthiness of the ISL or something else , please educate me )

 

[2informaticos]

The purpose of the forum is to assist people on their repairs.
Many times I explain even WHY and HOW, but this cannot replace a training course...

 

[JohnB8812]

Look at the schematic and tell us WHY those pins are important. Hint, they both should be low resistance

 

[nelo1012]

diode mode to ground pin2- 1.94 & pin 1-goes back to .OL

resistance (ohm scale) between pins 17/18 3.7ohms and 27/28 20.5 ohms of U7100.

 

[2informaticos]

"diode mode to ground pin2- 1.94"
You cannot get that reading with red probe at ground...

Post some voltages for U7100; 1, 2, 3, 9, 12, 13, 14, 15, 19, 20, 27.
Also check L7130 voltage removing F7140.