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This machine was exposed to liquid and would not start up. It initially presented with corroded left speaker amps, a shorted backlight driver UP800, as well as liquid-damaged trackpad. After cleaning and replacement of speaker amps UR660/UR630/UR600 and UP800 the machine is functional except...

This 820-02536 came in with 2 of 3 CD3217s shorted. I replaced all 3 CD3217s from a donor board, along with the 2 TBT ROM chips (U5560, UF260). Now the machine is fully functional except for the data line on USB port 1. Charging works on this port and it provides external 5V, just does not mount...

This 820-02536 presented with areas of liquid damage in the R_SPKRAMP area near UN000. I removed two corroded caps that had shorted PPBUS_AON and PP1V25_AWAKE_NAND to ground. Now, connecting a charger gets PPBUS of 12.3V and 5.1 on USB-C. The charger gets to 20V but as soon as it does, the...

This A2681 2022 board came in with liquid damage in the PP5V_S2 area and some other small spots. After cleaning, I replaced a misbehaving UC300 and the machine now chimes and starts up. Trackpad and keyboard are nonfunctional, but I’ll troubleshoot that separately. The main issue is that...

This logic board had a shorted Ocarina power supply chip U9580. After replacing it, both NAND chips for SSD1 are getting hot and show multiple shorts to ground. It don't have a donor board at hand for NAND replacement. What's the best way to convert this board to only use SSD0 (I assume with...

This board has had prior work done on it; I expect it was liquid-damaged. Several power rails were shorted, which I fixed: replacement of U8510 removed a short on PP3V3_G3H_RTC, and replacing U7800 removed a short on PP3V3_G3H. PPBUS is 12.3V but briefly dips to 9V every second or so. No...

This one has me stumped, though it looks like it should be an easy fix! Customer brought in an A1989 with a bit of liquid damage, which I cleaned up. It starts up and runs off a charged battery but does not recognize the charger on any of the 4 ports. Without a battery, all USB-C ports show...

This liquid-damaged Air has no trackpad and no keyboard. I need help troubleshooting. I already tried a known-good trackpad cable and a good keyboard without success. A known-good logic board in the same topcase shows functional keyboard & trackpad, so the topcase and daughter board should be...

This is my first board with the M2 architecture. This 2022 Air arrived with liquid-damaged USB-C port connectors and a few small spots of corrosion on the logic board. After cleaning, I found a short on LP800 and removal of the backlight controller UP800 removed the short. Now the board sits at...

This A2179 Air arrived dead after customer dropped it. One of its USB-C ports showed 20V, the other 5V. I replaced both CD3217s from an identical donor board and the machine appeared to work fine. However, when the computer is shut down, the battery continues draining (about 10-15% in 6 hours)...

This MacBook originally showed a short on PPBUS, which I traced to one of the CPU power drivers (U7410). Replacing it removed the short. Now the trackpad clicks and the fans are spinning, but it doesn't start up. PPBUS is 12.57V and the USB-C meter reads 20V and 2-3A (without a battery...

Board had minor liquid exposure in the USB-C area of the XA port. PPBUS was 80Ω to ground. I found a shorted speaker amp (U6550) and replacing it removed the short on PPBUS. I replaced all components with possible corrosion in the USB-C area around U3100, including the CD3215. Now, all 4 ports...

This 820-00850 board has 3 of 4 ports at 20V. The remaining port (USBC_TA) cycles between 5V and 0V when plugged in one way, and remains unresponsive when plugged in the other way. I checked all relevant LDO and power lines and found no shorts. What component could cause this plug asymmetry?

This 820-01700 board arrived with a single misbehaving USB-C port. I found a shorted CD3215, which I replaced with a location-matched chip from a donor board. Now all 4 ports charge the battery and power external USB drives but don’t allow for any data transfer. External drives are recognized...

This 820-01700 board arrived stuck at 5V USB-C. I found a short on the SSD0 NAND chips: it shows 3Ω to ground on L9530 (P1V8_SSD0) and 2Ω on L9580/1 (P2V5_SSD0). When I temporarily remove L9530 and L9580/1, I get 20V on USB-C (0.03A) and PPBUS is 12.6V. But no chime or startup. Before I...

This non-damaged 820-01700 board is stuck at 5.2V 0.04A on all 4 USB-C ports. I have PP3V3_G3H_RTC_X and all 3.3V and 1.5V LDOs. PPBUS is 12.3V. PP1V8_SLPS2R and PP1V1_SLPS2R are missing but pulse every second without stabilizing. Does this point to an issue with the PMIC U7800? How to best...

This 2020 M1 machine came to me for battery replacement. Works fine now except I can't get the Touch Bar to turn on. The Touch Bar works fine with another logic board in the same topcase. I don't have the customer's password, but the Touch Bar should illuminate on the login screen, correct...

Customer states that this A1707 machine experiences intermittent keyboard glitches. Inspection showed nothing strange and no liquid damage. However, camera and light sensor are nonfunctional. I verified that the ferrite bead L4004 is good, PP5V_S0_ALSCAM_F is at 5.1V, and the I2C data lines...

This board had minor liquid damage in the area around U9080 (NAND power supply). PPBUS is 12.6V. No shorts on the big coils. G3S rails are present. PP2V5_NAND_SSD0 is 2.5V. Trackpad clicks. DFU Restore times out (the board exits DFU mode during the Restore).

No obvious liquid damage on this board. PPDCIN_G3H cycles between 5V and 0V several times a second. PPBUS cycles between 0V and 12.3V. When I connect a battery, USB-C is around 20V and PPBUS is around 11V. No shorts on major coils, but I found the Ocarina PMIC chip U9000 getting hot. Could a...