Recent content by fixupp

With battery connected. 5v and 0.45a stable. Pbbus-aon stable at 12.35v All LDOs are not short, and pulsing the voltage. Look like the U8100 try to turn on and off

PPBUS_AON: 9-12.3v, pulsing when the apm is from 0-0.45a 3V8-_AON: 3v8 stable.

Water-damaged MacBook. Main areas ( U8100 U7700) are not affected. 5V Cycling between 0.00 and 0.45a. Check under the thermal camera U8100 pulsing hot. PP1v8_S2 0v, no short. Other U8100 and U770 LDO outputs are not short and pulsing.

Hi, any suggestions?

LT400 replaced with a new one. All LT20x are fine, with correct voltage. no issue with power rails on JT201. Any idea where to check? and is the no haptic feedback related with keyboard not working?

Update: I fixed the board. The pad underneath of R8450 is corroded so there is no PBUS_DIV then no PBUS_DIV_SNS_R. Had to jump a wire as the pad for PPBUS_AON is gone.

Sorry board number: 820-02536 I have replaced the components near the trackpad connector JT400. I can see resister burned and need to clean the pad before replacing with new one. Replaced the followings: RC852, RC832, RC850, UC850 UC840 UT380 UD230 UT3B0 UT3C0

I tried to replace the damaged component from a donor board, testing with multiple known working trackpads, trackpad cables, keyboards, small keyboard boards, and a new lid sensor, but still can't get the keyboard working. Trackpad works, but no haptic feedback

U8100 Imput: NO SHORT PP3V8_AON_MPMU_ISNS_VIN 3v8 PPVDD_LDO20_14_8_3: 0v no short PPVDD_S2SW_VDD2H: 0v no short Output: NO SHORT PP1V8_AON: 0 no short PP3V3_S2_LDO: 0v PP1V2_AWAKE_PLL: 0v PP1V8_AON_MPMU: 1v8 PP1V2_AON_MPMU: 1v2 PP3V3_AON: 0.3-0.5v PP0V855_S2SW_CIO: 0v PP3V3_S2SW_SNS: 0v...

No it is not recognized in DFU. Does it mean I have a short somewhere? Which page where I can find all the LDOs?

found the issue with PP3V3_AON. PP3V3_AON jumping from 0.3 to 0.9 but no short. No short and diot value corrects MPMU_BSTLQ_LX 3.8 PP5V_MPMU_BSTLQ_XW 5v PP1V2_AON_MPMU 1v2 PP1v8AON: 1v8

Water damage board around U5700, Q5800 5820 5840 and U8100. Replaced U5700 then have 3.8v on PP3v8AON. PP3V8_AON_MPMU_ISNS_VIN is 3.8V P5vs2 and others S2 rails: 0V. U8100 is fine as I tried to install this IC to other M2 board then it is working. U8100 seems to not turn on. I have checked all...

with new BIOS file still same issue. I will buy the Apple Data Recovery tool to back up the data. Customer installs both Win and Mac OS, is it possible to retrieve data from Window

Thanks for the reply. Already tried with new bios but same issue. PPVCC_S0_CPU stable at 1.05v after 20s PLT_RST_L: at first 3.v3 then go low 0v in arround 6 secs then back to 3.3v

Hi, Im just start learning motherboard repair, please assist. I have this board with no water damage and mint condition. Customer said it was suddently dying while working. It takes 20v 1a with no battery or 20v 4a with battery connected. No chime, not turn on, trackpad clicks. the board is...