I got an 820-01958 after liqiud spill. Motherboard was not affected at all, no spots or corrosion, only audio board had some corrosion. Anyway board was completely dead. I have found out, that PP1V8_G3S is shorted in U6400. I have replaced that chip and short is gone. Board switches to 20V, takes ~0,07A and... that's it. I have noticed, that there is no CPU VCORE and PP1V1_S3 is not present too. Further measurements are below:
Resistance on PP1V1_S3 is 4,6 ohm (0,003V in diode mode). I think it's far too low, no matter that the line is low voltage (I don't have the same working board but for comparison on 820-01521 resistance of line PP1V2_S3 is 0,9k ohm and 0,220V in diode mode). Obviously I can't see anythyng warming up on thermal camera, as the line takes about 0,045A.
other readings:
PPBUS_G3H - 12,62V
PP3V3_G3H - 3,29V
PP5V_G3S - 5,10V
PPVCC_NAND_SSD0 - 2,52V
PP1V8_G3S - 1,81V
I can put the board to DFU mode, but can't revive or restore it. Could you please confirm if PP1V1_S3 resistance is too low or normal?
Resistance on PP1V1_S3 is 4,6 ohm (0,003V in diode mode). I think it's far too low, no matter that the line is low voltage (I don't have the same working board but for comparison on 820-01521 resistance of line PP1V2_S3 is 0,9k ohm and 0,220V in diode mode). Obviously I can't see anythyng warming up on thermal camera, as the line takes about 0,045A.
other readings:
PPBUS_G3H - 12,62V
PP3V3_G3H - 3,29V
PP5V_G3S - 5,10V
PPVCC_NAND_SSD0 - 2,52V
PP1V8_G3S - 1,81V
I can put the board to DFU mode, but can't revive or restore it. Could you please confirm if PP1V1_S3 resistance is too low or normal?
