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Hello everyone..
This laptop came with symptoms:
- no response to power button on battery
- when AC adapter is connected, charge and power leds comes on then power led goes off after 1 second while charge still on
- no response to power button with AC adapter connected
I've tried removing and reconnecting AC adapter for multiple times and the board started, it happened only for one time
removed the board and start checking and tracing the problem,3.3v is ok at the power button, +3VPCU is on but found that SPI GD25B64 has 0v on pin 8 with no shorts to ground (comes from +3v_s5), reconnecting AC adapter rises +3v_s5 for couple of seconds then it drops to 0v..
removed GD25B64 and +3v_s5 rises and keeps on but no power led, replaced with new flashed chip and it behaves the same, +3v_s5 rise then fall, this is where I've noticed that power led stopped working, soldered the original bios chip but power led stopped behaving like it was before ..
traced down +3v_s5 to find that it's enabled by S5D signal by S5_ON signal and both are 0v, reconnecting AC adapter and S5_ON/S5D comes on for couple of seconds then goes off..
tried replacing PU4 and PQ1,PQ2,PQ3,PQ4,PQ5,PQ6,PQ8 but nothing changed..
found that SYS_SHDN# is always high, is that normal ?
Where should I dig ?
removing PR1,PR3,PR16 and PQ3 should bring S5D as always live with all driven +3v_s5 and +5v_s5 and +1.05v_s5 with no need to S5_ON signal, is that correct ? is it a good idea to try ?
edit: replaced RTC Clock Y2 and AS393MTR-E1 PU6, tried both GD (originally installed on board) and Winbond (used in schematics) BIOS chips,,,, no avail
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