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SOLVED: A1990 820-01814 20V 0.01A after liquid spill around U3100
- Thread starter it-solve
- Start date
All USB-C ports get the same current consumption?
Compare diode mode readings on U7800 coils with good board.
Also check SSD power rails.
Compare diode mode readings on U7800 coils with good board.
Also check SSD power rails.
it-solve
Member
No shorts there either. Yes, same behaviour and current consumption on all ports.
0.9, 1.1 and 2.5 are present on SSD lines
CPU_AWAKE are around 10Ohms - 0.5V
P0V8SLPDDR are at 35Ohm range - 0.8V
The remaining are over 100Ohms.
Al coils around U7800 provide voltage apart than PPVVPRIMCORE L7821/2
I have replaced U3100 again, and now gets 20V 0.01A almost consistent across all 4 ports. Sometimes just takes ages to transition from 5V 0.5A to 20V 0.01A. Disconnect and connect the adapter and then goes straightforward. T2 is getting warm
Is T2 also responsible for PD handshake or only CD32's?
0.9, 1.1 and 2.5 are present on SSD lines
CPU_AWAKE are around 10Ohms - 0.5V
P0V8SLPDDR are at 35Ohm range - 0.8V
The remaining are over 100Ohms.
Al coils around U7800 provide voltage apart than PPVVPRIMCORE L7821/2
I have replaced U3100 again, and now gets 20V 0.01A almost consistent across all 4 ports. Sometimes just takes ages to transition from 5V 0.5A to 20V 0.01A. Disconnect and connect the adapter and then goes straightforward. T2 is getting warm
Is T2 also responsible for PD handshake or only CD32's?
CD3215 chips require to communicate with T2, before switching to 20V.
Sometime DFU can solve such problem.
Sometime DFU can solve such problem.
it-solve
Member
Are you aware if this model needs a battery to turn on?
I managed to FORCE_DFU and revived the system. While it is connected to power I managed to load the system, it shows the battery needs service but charging. Pulling 2A charging current. But the minute I disconnect the charger it shuts down and doesn't turn on anymore. with USBc staying at 20V 0.01A.
With disconnected battery same
Did it twice on revive and both times the minute I disconnected from charger, wont turn on until DFU revive.
I managed to FORCE_DFU and revived the system. While it is connected to power I managed to load the system, it shows the battery needs service but charging. Pulling 2A charging current. But the minute I disconnect the charger it shuts down and doesn't turn on anymore. with USBc staying at 20V 0.01A.
With disconnected battery same
Did it twice on revive and both times the minute I disconnected from charger, wont turn on until DFU revive.
Not sure, should test with good battery.
it-solve
Member
I can confirm, that this model doesn't turn on without a battery. 20V 0.01A when the battery is not connected.
I've replaced the battery and all is good. Thank you for your help @2informaticos
I've replaced the battery and all is good. Thank you for your help @2informaticos