Recent content by chrislewis85

  1. C

    820-00840 no POST

    0.055v diode mode 46.8 ohm
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    820-00840 no POST

    L7930 = 1.78V L7960 = 0V
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    820-00840 no POST

    L7670 = 5.09V L7690 = 3.3V L8410 = .01V L7030 = 7.08-7.11V (seems to roll up and down) L7730 = 1.04V L7430 = 0V L7410 = 0V L7420 = 0V L7210 = 0V L7220 = 0V L7370 = 0V L8060 = 0.99V L7900 = 1.00V L8030 = 1.2V L7960 = 0V
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    820-00840 no POST

    Worth mentioning after a short while current increases and settles at 0.05A. I'm getting S0 rails too both 3V3 and 5V
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    820-00840 no POST

    Yep, I have 3V3_S5
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    820-00840 no POST

    Hi guys, Got an 820-00840 that I got for new screen (usual flexgate problem) Noticed that machine has a 'cold boot' issue where it randomly powers off or restarts during use, especially when cold booting. First few times it struggles to even get to login screen. After a warm up period is...
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    820-00840 no image

    It has previous repair to 3V3_S4 so it is highly likely thats the case. When I pulled R6999 the short was on the 'right' side (so a LOT of potential components) Voltage injection best method to see what gets abnormally hot?
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    820-3437-B not powering

    Diode mode to ground at L7560 = 0.344v 3v3_SUS is 0v U7501 looks clean (but also fresh solder on test points in the area so likely board has been repaired previously)
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    820-00840 no image

    Hi 2info, Tried PRAM reset and no difference - audio hardware on the board is not detected. Having left the board overnight it is now stuck at 5V again and won't jump to 20v on either port. Diode mode on 3v3_G3H is 0.101v so doesn't appear shorted now. Something bizarre going on because I had...
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    820-3437-B not powering

    Hi guys, Got a 3437-B which had fluid damage around U1950. Cleaned area and replaced U1950. Getting green light but no fan spin. Rails so far as follows: PPBUS_G3H = 8.56V PP3V3_S5 = 3.0V PP5V_S5 = 5.0V PP3V3_S4 = 0V Struggling to understand on schematic where S4 rails will...
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    820-00840 no image

    While waiting for del of a bench PSU to check this - tried it again and the damn thing has powered on and booted. I still have a short somewhere as it intermittently reboots. Only clue I have is that there are now no audio devices listed in output! (And no chime now whereas before audio worked...
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    820-00165 no power

    U7100 changed, R7101 tested ok but changed anyway as I had some brand new ones. No change, board still not powering on
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    820-00165 no power

    Sorry, for some reason I though I had an 85W charger connected not a 60w, so 16.44 is obviously perfectly fine Getting OL diode mode to ground on both 19 and 20
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    820-00840 no image

    This board is now becoming a nightmare. While testing for DP_INT_HPD board stopped powering on and is now stuck at 5v, with a short on PP3V3_G3H. Removed R6999 and it the short is on the "right side" and so could be anywhere. Any advice for trying to locate the short?
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    820-00165 no power

    Hi 2informaticos, Fair enough, I was expecting nearer to 18v thanks for clarifying! Diode mode PPBUS_G3H = 0.130v U7100: 1: 15v 2: 16.41v 3: 4.31v 9: 0.02v 12: 3.37v 13: 3.34v 14: 3.34v 15: 0.11v 17: 0.5v 19: 0.5v 20: 0.3v 27: 1.38v
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