Partial summary:
- GOOD NEW IS: Automatic power on when AC pluged in reason was a bad CMOS battery pin. When I have mesured the cmos battery right in the connector plus side it was only 0.3 volts. After bended the pin 3.05v presented and it won't start automaticaly when AC plugged in.
- BAD NEW IS: durring the last bios chip resoldering I have made something that made the laptop not responding to start button.
Next step is to find out why I cannot turn on the laptop.
I hear a high pitched noise when AC plugged in somewhere around the bios chip but can't realy tell where its coming from.
Inspecting with microscope... to be continued.
After watching closely the integrated ram i noticed a high pitched sound is coming from around U1501 RAM chip.
So My guess is one of C1316, C1412, C1522, C1424, C1414, C1415 is partialy wrong.
Im going to remove them one by one and see if the high pitched sound disappears. If you have better idea then tell me please.
I Have noticed something. H_DRAM_PWRGD is a signal that supposed to go from PCH to CPU. I'm I right?
So why does it not going to CPU? Both R0338 and R0341 are not existing Resistors.
I managed to get a good board and did some readings on resistors.
The main differences are:
R0347 - 10kohm ( 90Kohm on good board)
R0338 - 3.2Kohm (this was 1.7Kohm when i started the diag and 1.75Kohm on good board)
R0336 - 3.1Kohm (1.75 Kohm on good board)
Should I replace R0338 and R0336 with 1.8Kohm resistor?
What about R0347? Is iteven possible that a resistance is lowered when a resistor fails?
I managed to get a good board and did some readings on resistors.
The main differences are:
R0347 - 10kohm ( 90Kohm on good board)
R0338 - 3.2Kohm (this was 1.7Kohm when i started the diag and 1.75Kohm on good board)
R0336 - 3.1Kohm (1.75 Kohm on good board)
Should I replace R0338 and R0336 with 1.8Kohm resistor?
What about R0347? Is iteven possible that a resistance is lowered when a resistor fails?
Changed battery on multimeter and Remeasured everything.
R0347 - 89.7Kohm on bad boards so its good.
R0338 - 3.75Kohm (1,75 on good board)
R0336 - 3.2Kohm (1.2 on good boad)
Thinking on what has changed durring the u0303 replacement.
It is possible that R0336 resistance is risen because of u0303 replacement heat was too high.
Since R0338 is a non existing resistor and it can be that it connected through a 0.5kohm resistor somewhere to R0336 and it raised because R0336 raised.
Ordered new 1.2Kohm resistor with sample book (30 days) be back withthe result when replaced R0336.
Replaced R0336
Now Resistances are same as a good board.
Only thing that has changed is H_DRAM_PWRGD risen to 0.74v
Searched for more clues on the board and found that PU8501 nvidia power management has a short on pin #10
P_NVVDD_FBRTN_10 0v and short tu ground.
pins readings are:
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