bighead
New member
Hi All,
So I have this nice Retina here with liquid damage.
I cleaned it. Battery is dead.
It was powering on, but no CPU VCORE.
I checked the power to U7200 and I saw R7202 was corroded. I changed it and it turned on for a sec or two and turned off.
PP3V42_G3H was 70-80 Ohm short to ground. I found a bad corroded cap C1950. I changed it with U1950.
It turned on for a second again. I was able to turn it on with SMC bypass, but after 10 seconds it turned off. Never could turn it back on.
I found SMC crystal wasn't oscillating and there was no voltage on it. No short! I didn't have the same board so I took the SMC off of the 820-3332.
After I replaced the SMC the crystal is oscillating, but still not turning on. The fan just barely spins up. This is not a turn on-off loop thing.
This tries to turn on, turns off and it does not try to turn on again. I tried SMC bypass mode, but same thing. I couldn't find any short.
It still powers on if I remove R7202, just of course no CPU VCORE.
Any ideas?
Thank you!
So I have this nice Retina here with liquid damage.
I cleaned it. Battery is dead.
It was powering on, but no CPU VCORE.
I checked the power to U7200 and I saw R7202 was corroded. I changed it and it turned on for a sec or two and turned off.
PP3V42_G3H was 70-80 Ohm short to ground. I found a bad corroded cap C1950. I changed it with U1950.
It turned on for a second again. I was able to turn it on with SMC bypass, but after 10 seconds it turned off. Never could turn it back on.
I found SMC crystal wasn't oscillating and there was no voltage on it. No short! I didn't have the same board so I took the SMC off of the 820-3332.
After I replaced the SMC the crystal is oscillating, but still not turning on. The fan just barely spins up. This is not a turn on-off loop thing.
This tries to turn on, turns off and it does not try to turn on again. I tried SMC bypass mode, but same thing. I couldn't find any short.
It still powers on if I remove R7202, just of course no CPU VCORE.
Any ideas?
Thank you!
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