Recent content by nik1981

  1. nik1981

    820-00928 With a power cycle issue

    I have an 820-00928 that when plugged in jumps from 5v to 20v and pulls up to 1.8a but then reboots the charger back to 0.2a. The screen shows the battery and then goes off again when the charger drops back to 0.2a Does this on all 4 ports. I've checked U3100, U3200, UB300, UB400 and the main...
  2. nik1981

    820-01700 with 5v only [SOLVED]

    Replaced U3100 today and the low resistance went away, the MacBook works perfectly now. Thank you for your help as always 2informaticos.
  3. nik1981

    820-01700 with 5v only [SOLVED]

    UB300 & UB400 seem fine and they're similar to each other
  4. nik1981

    820-01700 with 5v only [SOLVED]

    For U3100: C3108 - PP3V3_UPC_XA_LDO is only 0.021v C3104 - PP1V5_UPC_XA_LDO_CORE is only 0.019v but for U3200, the same caps are around 0.453v So U3100 is the problem?
  5. nik1981

    820-01700 with 5v only [SOLVED]

    Hello, I have an 820-01700 that won't power on. No signs of liquid. Just stopped charging. With the board out, on 3 of the ports I get 5.12v 0.37-0.39a and the 4th port (left side front) I get 5.14v but only 0.13a. With the 3 ports I get 12.2v constant on PPBUS but 0v on the low port. If I...
  6. nik1981

    A1708 820-00840 No backlight (SOLVED)

    Hi 2informaticos, Thank you for the quick reply. I just sorted it thankfully. It tested as low ohms on PPVOUT_S0_LCDBKLT so I decided to inject 5v into that line and have a look on FLIR The issue was with capacitor C8470 shorting. Replaced and now works fine. I was having an off day obviously...
  7. nik1981

    A1708 820-00840 No backlight (SOLVED)

    I have an 820-00840 with no backlight. Tried multiple screens but no difference. Took the board out and it seems that Q8400 is getting its 12.9v PPVIN on pin 4 but the hate voltage is also 12.9v on pin 3 so isn't opening. I can't seem to figure out why pin 3 isn't dropping. The resistance...
  8. nik1981

    A1932 Keyboard replacement

    Yeah, no access to AST though unless you're Apple Technician
  9. nik1981

    A1932 Keyboard replacement

    Bluetooth Apple keyboard from an iMac works fine. Haven't tried a USB one. I thought about replacing the trackpad also but this keyboard was "a new part" from a supplier rather than a specific machine. I've installed Karabiner and that has got them working but its not the best solution long...
  10. nik1981

    A1932 Keyboard replacement

    Hello, does anyone know a way around the function key mapping issue on replacement keyboards? This A1932 has a replacement keyboard but without access to the AST 2 server, I can't see a way around getting the function keys to work again. Just to be clear, the keyboard isn't faulty, its just...
  11. nik1981

    820-00928 20v 40ma

    With the battery plugged its pulling 20v 3.6a but I suppose thats just battery charging only as everything just stays pulsing
  12. nik1981

    820-00928 20v 40ma

    SMC Bypass does nothing unfortunately
  13. nik1981

    820-00928 20v 40ma

    Hi 2informaticos, thank you for your help. L7330 and L7960 are pulsing but the multimeter isn't quick enough to catch the peak (possibly 0.8v-1v). L8000 has nothing on pin 1 P1VS4_PHASE but does have 1v constant on pin 2 PP1V_PCH_REG_R P12V_SSD_VPP_SW & _L are holding at 0.15v and pulsing...
  14. nik1981

    820-00928 20v 40ma

    Hello, I have an 820-00928 with 20v and only 0.04a which jumps to 0.40a and back again every 15 seconds. No obvious signs of liquid and wont start on SMC bypass Testing board on the side only with only a dc in board connected, I get: PPBUS_G3H = 12.52 PP3V3_S0 = pulsing ALL_SYS_PWRGD =...
  15. nik1981

    Not a Mac but a charging circuit issue

    I've spent the last week trying to sort my sons brand new Acer laptop for a charging issue after liquid damage. Originally it wouldn't turn on but I found shorting caps on the 19VB_CHG circuit. Replaced those with the same and the laptop fired up fine, works on charger or battery but won't...
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