Hi everyone,
I just bought a dead Sony VAIO Duo 13 ... and I'm willing to restore it to its past glory!
The device has been already opened, and a clear sign of this is a broken flat cable that connects the power switch and the charge led to the motherboard.
Unfortunately this seems to be just one of the laptop's problems, here's my troubleshooting.
I disconnected everything from the motherboard (even the main battery), except the fan.
Charger's output is 10.5v. This voltage is present at the motherboard, and passes the first fuse.
Voltage at the power button pin is 3.3v as soon as i attach the power supply.
I checked the voltage at the various power inductors. It is 0v, but if I pull down to ground for some seconds the power button pin, I get 5.1v and 3.3v at two of the coils (tomorrow I'll try to contextualize with some pics).
All other power inductors remain at 0v even after simulating the power button pressure. Nothing seems to get particularly hot in this case.
If the main battery is connected to the motherboard, something interesting happens. One third power inductor goes to 8.5v. However, after simulating the power button pressure it becomes hot (battery pack rating is 7.5v), along with an adjacent mosfet and a couple of passive components (and battery charger IC, BQ-24735) on the other side of the board (tomorrow I'll try to contextualize with some pics).
No power at the Winbond flash, no power at USB ports.
Some questions for you people:
1. Is it possible that this laptop can't be powered on without battery? Why the "getting hot" fault is showing only in this occasion?
2. It seems a possible case of a shorted cap ... but why does it show up only if the battery is connected?
3. Why 5.1v and 3.3v show up only after power switch is pressed? Even though somehow a low power 3.3v rail is always there, since it's always present at the power switch (is this a sign that the Super I/O chip is good?).
4. Someone has a board diagram for this board?
5. I checked some enable signals (I'll repeat the test tomorrow though) at voltage regulator TPS-51367 and it seems 0v ...
I'll dedicate some more time to study it asap, please follow this thread and give me suggestions!
I just bought a dead Sony VAIO Duo 13 ... and I'm willing to restore it to its past glory!
The device has been already opened, and a clear sign of this is a broken flat cable that connects the power switch and the charge led to the motherboard.
Unfortunately this seems to be just one of the laptop's problems, here's my troubleshooting.
I disconnected everything from the motherboard (even the main battery), except the fan.
Charger's output is 10.5v. This voltage is present at the motherboard, and passes the first fuse.
Voltage at the power button pin is 3.3v as soon as i attach the power supply.
I checked the voltage at the various power inductors. It is 0v, but if I pull down to ground for some seconds the power button pin, I get 5.1v and 3.3v at two of the coils (tomorrow I'll try to contextualize with some pics).
All other power inductors remain at 0v even after simulating the power button pressure. Nothing seems to get particularly hot in this case.
If the main battery is connected to the motherboard, something interesting happens. One third power inductor goes to 8.5v. However, after simulating the power button pressure it becomes hot (battery pack rating is 7.5v), along with an adjacent mosfet and a couple of passive components (and battery charger IC, BQ-24735) on the other side of the board (tomorrow I'll try to contextualize with some pics).
No power at the Winbond flash, no power at USB ports.
Some questions for you people:
1. Is it possible that this laptop can't be powered on without battery? Why the "getting hot" fault is showing only in this occasion?
2. It seems a possible case of a shorted cap ... but why does it show up only if the battery is connected?
3. Why 5.1v and 3.3v show up only after power switch is pressed? Even though somehow a low power 3.3v rail is always there, since it's always present at the power switch (is this a sign that the Super I/O chip is good?).
4. Someone has a board diagram for this board?
5. I checked some enable signals (I'll repeat the test tomorrow though) at voltage regulator TPS-51367 and it seems 0v ...
I'll dedicate some more time to study it asap, please follow this thread and give me suggestions!
Comment