Packard Bell Dot S (Quanta ZE7 mainboard) liquid damage repair
I had two laptops with liquid damage brought in by the same guy. The Acer was an easier fix and was done the same day, but this one required purchase of a component so i only got around to getting it done now.
Damaged parts: U3 RT8223M with no output, PC47 visibly corroded, PR190 with a hole in it. Later i found out that it also had no input even after i replaced the resistor PR190 (the via connecting to pin 16 VIN went open), thus the wire you see in the photos was necessary.
Replaced U3 RT8223M with RT8223B, they are one and the same. Then i had the LDOs going but 3VPCU and 5VPCU still not up. Checked ENC pin, ok. Removed power and found 5VPCU completely shorted. Removed L25 and the short remained on the power supply side (phew). Removed a few ceramic caps but no luck. Then i decided to apply power to the short with a large 3.7v lithium battery. Had huge current draw (6.5A), and after a few seconds PC46 220u 6.3v poly cap fizzled and produced a very nasty smell.
Removed PC46, short was gone. Did not have poly cap that small in height, so i replaced it with a 330uF tantalum. Applied power, hit the button and got some lights. Plugged in the screen and we have picture!
Put in a hard drive and it booted just fine. Battery's charging too.
That's all for this one.
Schematic https://www.badcaps.net/forum/showthread.php?p=1263291
The keyboard is shorted too (makes the netbook beep continuously and no keys work) but that isn't my problem.
You see in the pic i tested with an USB keyboard and it works fine.
Damaged parts: U3 RT8223M with no output, PC47 visibly corroded, PR190 with a hole in it. Later i found out that it also had no input even after i replaced the resistor PR190 (the via connecting to pin 16 VIN went open), thus the wire you see in the photos was necessary.
Replaced U3 RT8223M with RT8223B, they are one and the same. Then i had the LDOs going but 3VPCU and 5VPCU still not up. Checked ENC pin, ok. Removed power and found 5VPCU completely shorted. Removed L25 and the short remained on the power supply side (phew). Removed a few ceramic caps but no luck. Then i decided to apply power to the short with a large 3.7v lithium battery. Had huge current draw (6.5A), and after a few seconds PC46 220u 6.3v poly cap fizzled and produced a very nasty smell.
Removed PC46, short was gone. Did not have poly cap that small in height, so i replaced it with a 330uF tantalum. Applied power, hit the button and got some lights. Plugged in the screen and we have picture!
Put in a hard drive and it booted just fine. Battery's charging too.That's all for this one.
Schematic https://www.badcaps.net/forum/showthread.php?p=1263291
The keyboard is shorted too (makes the netbook beep continuously and no keys work) but that isn't my problem.
You see in the pic i tested with an USB keyboard and it works fine.
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