820-01598 20v 0.080ma

TBFix

Member
No sign of spillage/damage. Customer said they had just finished installing os and it would not power up again. PPbus is 12.6v I have tried in dfu mode and forced dfu mode but still get amrestore error. SSD voltages present PP1V8_IO_SSD0, PP0V9_SSD0 , PP2V5_NAND_SSD0 on both nand chips.
 

TBFix

Member
Check for short on all big coils.

Connect charger cable, before DFU cable.
I changed both the nands and I dfu no problem and now it boots and chimes but has no backlight so investigating that now. I have external video only.
 
Last edited:

TBFix

Member
Hi I checked J8500 diode mode and all seem ok no shorts.
PP5V_S0SW_LCD = 5v
PPVOUT_S0_LCDBKLT = 0v
PPVIN_S0SW_LCDBKLT_R = 12.5v
LCDBKLT_EN_L = 12.48v
PP5V_S0_BKLT_A = 5v
PP5V_S0_BKLT_D =5v
EDP_BKLT_EN = 0v

I have also replaced U8400
Any ideas?
 
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