Recent content by VinceLx

  1. V

    820-00165 no fan

    Indeed. I heat the board square cm per square cm, I finally found that heating U7200 allowed to start the board. Tiny short between pin 10 and 11... Now ok, thanks!
  2. V

    820-00165 no fan

    Cold, the board does not want to start. Again, no pulses on SMC_DELAYED_PWRGD I tied again together pins 5 & 6 with U1950 present, I have pulses on pins 7 and 3, but the board does not start, SMC bypass or not, just fan spinning 1 second, as before. Don't know where to go. It worked, I could...
  3. V

    820-00165 no fan

    Finally found a tiny corrosion spot around C4090 C4691 linked with PP5V_S4RS3, which gave also a pulse previously. Cleaned around and now the board starts alone, let's see for how long. Thanks for this very detailed investigation! Always learning
  4. V

    820-00165 no fan

    I tied them without U1950, and for some reasons I had pulses on SMC_DELAYED_PWRGD Reinstalled U1950, I could start the board (blinking folder) by triggering SMC_ONOFF_L, with power supply giving 700mA, a bit higher than normal. The board did not start alone when giving power. When trying later...
  5. V

    820-00165 no fan

    Pulse on pin 7 ok, no pulse at pin 3. I had pulses on SMC_DELAYED_PWRGD, but not at each trigger of SMC_ONOFF_L Removed U1950, I got a couple of pulses on SMC_DELAYED_PWRGD, then no more. Do this pulse should appear at each SMC_ONOFF_L trigger? R5191 ok Fan spins first low speed a few seconds...
  6. V

    820-00165 no fan

    I tested in SMC bypass mode, fan spins 1 second when triggering SMC_ONOFF_L Power supplies have pulses: PP3V3_S4: pulse 3.3V PP3V3_S3: pulse 3.3V PP1V2_S3: pulse 1.2V PP1V8_S3: pulse 1.8V PP1V05_S0: pulse 1V PP5V_S0: pulse 5V PP3V3_S0: pulse 3.3V
  7. V

    820-3437 no fan, pulsing

    Q8150 removed, pulse of 3.4V on ALL_SYS_PWRGD, exactly same behaviour in SMC bypass mode, fan is spinning half a second, then quarter fan spin, and repeat
  8. V

    820-3437 no fan, pulsing

    There are pulses of 3.4V at pins 7 & 3 of U1950, also on PLT_RESET_L
  9. V

    A1502 820-4924 Question mark folder

    Without internal SSD, did you try to boot on a old OS X (e.g 10.13) in a USB key? I had cases where internal SSD prevented to recognize other boot possibilities
  10. V

    820-00165 no fan

    You mean the same for PM_SLP_S3_L? There is also a brief pulse from 0 to 3.4V Power rails: from PM_SLP_S4_L : P3V3S3_EN P1V8S3_EN DDREG_EN all have a pulse at 3.4V from PM_SLP_S3_L : CPU_VCCST_PWRGD: pulse at 1V P5VS0_EN P3V3S0_EN P1V05S0_EN all have a pulse at 3.4V
  11. V

    820-00165 no fan

    Indeed there is a brief pulse from 0 to 3.4V on PM_SLP_S4_L
  12. V

    820-3437 no fan, pulsing

    In SMC bypass mode: PPBUS_G3H=8.2V, the fan is spinning half a second, then quarter fan spin, and it starts again half a second, then quarter fan spin... Sometimes the fan is just ticking. I have pulses on L7520, L7630, L7430, L7310, L7320 No pulses on L3095 3.3V on L7560, 8.2V on L7130
  13. V

    820-3437 no fan, pulsing

    The board looks ok, no fan, power supply gives 20-30mA with pulses at 120mA every 3-4 seconds as if it wanted to start but cannot PP3V42_G3H=3.44V PPBUS_G3H=8.6V PP5V_S5=5V PP3V3_S5=3.3V PP3V3_SUS=3.3V PP5V_S4=bursts every 3-4 seconds no readable PP3V3_S4=bursts every 3-4 seconds at 3.3V...
  14. V

    820-00165 no fan

    PM_PWRBTN_L goes from 3.4V to 0.35V as long as SMC_ONOFF_L is shorted to ground Power supply goes shortly from 30mA to 50mA, nothing else
  15. V

    820-00165 no fan

    Yes, 3.3V ok
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