ameasere
New member
820-02100 with water damage, corrosion around U5200 but was cleaned with IPA. Device chimes, touchpad clicks, successfully negotiates from 5V to 19.5V and hovers between 0.006 and 0.4A. It will spike for only a second up to 1A, then immediately drop down to 0.1A - if left long enough, it will get stuck after power cycling once and sitting at 4.94V 0A.
During the first few stages, touchpad clicks and I can hear (quite loudly) "voiceover off" if I press the power button repeatedly. No picture on screen, no fan spin, and nothing over HDMI - though it does wake up the monitor over HDMI, but no picture is ever sent. Sometimes it will ramp up the fans to 100% and stay like that until power cycling, and others I get no fan spin at all.
Under thermal camera, the board is mostly cold. M1 RAM chips get a little warm at 30C, and a 25-30C signature from the shroud covering L5800/20/40 coils.
UN400 has a small black blob which I am unsure of - I understand from Louis Rossmann's prior videos that if this chip blows, it usually sends 12V to the NAND and ruins all chances of data recovery. I hope this is not the case. I have attached a photo of this strange blob.
Same symptoms with battery plugged in and unplugged.
Please do advise on any next steps to further check and diagnose.
Voltages observed
PPBUS_AON - 12.6V
PP3V3_AON - 3.3V
PP3V3_S2 - 3.3V
PP5V_S2_MAIN - 5.1V
PP3V8_AON - 3.8V
PP1V8_AON - 1.8V
During the first few stages, touchpad clicks and I can hear (quite loudly) "voiceover off" if I press the power button repeatedly. No picture on screen, no fan spin, and nothing over HDMI - though it does wake up the monitor over HDMI, but no picture is ever sent. Sometimes it will ramp up the fans to 100% and stay like that until power cycling, and others I get no fan spin at all.
Under thermal camera, the board is mostly cold. M1 RAM chips get a little warm at 30C, and a 25-30C signature from the shroud covering L5800/20/40 coils.
UN400 has a small black blob which I am unsure of - I understand from Louis Rossmann's prior videos that if this chip blows, it usually sends 12V to the NAND and ruins all chances of data recovery. I hope this is not the case. I have attached a photo of this strange blob.
Same symptoms with battery plugged in and unplugged.
Please do advise on any next steps to further check and diagnose.
Voltages observed
PPBUS_AON - 12.6V
PP3V3_AON - 3.3V
PP3V3_S2 - 3.3V
PP5V_S2_MAIN - 5.1V
PP3V8_AON - 3.8V
PP1V8_AON - 1.8V