thread top ad

Collapse

Announcement

Collapse
No announcement yet.

MBA A1466 820-00165 no green light, no boot

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • jurgenkoppen
    replied
    How does the Master Louis say it: Baddabing! Rebooted a few times, seems stabil!!

    Leave a comment:


  • jurgenkoppen
    replied
    And now, for something completely different: After I removed C7782, the LCD now is operational.....wtff?

    Leave a comment:


  • jurgenkoppen
    replied
    OK, I tested Q7706 which has voltage only on p2 ands p5, 3.3V each. Then I looked at C7782 which was corroded enough to nearly fall off....

    Leave a comment:


  • jurgenkoppen
    replied
    Yes, I do have the image, only it is very dark. I can run an external screen, so the machine is fine otherwise.
    I looked at some of the forum backlight info, and did some measurements. I have nothing on PPVIN_S0SW_LCDBKLT, 0V. So it must be what generates PPVIN_S0SW_LCDBKLT. I 'll keep digging...

    Leave a comment:


  • 2informaticos
    replied
    Do you get image on internal screen, only missing backlight?
    The forum is full with information about backlight issues, especially for 00165 boards...

    Leave a comment:


  • jurgenkoppen
    replied
    OK, I did throw the towel on the old logic board we discussed above, and bought a working one on Ebay. I know it is cheating, but wtf, I am a newbie and got tired of messing with it. Put in the new logic board,: it booted up fine for about 10 min, until I removed some fingerprints smudges on the LCD screen, upon which I lost my backlight. So I did the reseating of the connector, checked the fuse ,which is fine, and then assumed that the screen (which was the original screen in a water damaged machine), might have been compromised when it shorted, and bought another screen. But alas, I still have no backlight. The machine boots, runs well on an external monitor. Now if I could please have some help on finding what else might be the issue...So now I have a new used logic board, a new used screen, and a brand new battery...
    Last edited by jurgenkoppen; 06-25-2019, 05:42 PM. Reason: grammer

    Leave a comment:


  • 2informaticos
    replied
    Just buy a fake charger for the original board.
    It should then work with a simple short instead of D7012.

    Leave a comment:


  • jurgenkoppen
    replied
    Nevermind, she did boot up after all with my new logic board. Appears that the battery is fried and the machine will shut down immediately when I plug it in. The LCD screen was shaky, but stabilized and now is going without flicker....I am getting a new battery and call is a day.

    Leave a comment:


  • jurgenkoppen
    replied
    OK so have to admit defeat. I gave up on the board and the zener diodes, just purchased another logic board and just installed it. Still no light on the charger, no boot. Could it be the DC in board which is causing my problem? I also disconnected the keyboard when trying to boot, in order to make sure that no short in the keyboard would interfere. But nada.
    Last edited by jurgenkoppen; 04-10-2019, 11:31 PM.

    Leave a comment:


  • 2informaticos
    replied
    D7012 has a very low current for its zener voltage
    Bigger diodes could require higher current to enter in zener zone.
    Check datasheet specifications of the one you want to buy.
    0.25-0.5W will work for sure; probably 1W too, just try.

    You can short D7012 to ground and use fake charger, it should work...

    Leave a comment:


  • jurgenkoppen
    replied
    I can buy these diodes here in Canada, and get them faster than from China of course. Would a 1W diode be appropriate in this application? http://vi.raptor.ebaydesc.com/ws/eBa...=1552801163871

    Leave a comment:


  • jurgenkoppen
    replied
    It turns out that the 6.8V multidirectional diodes are not a replacement for the 6.8V Zener diode. Well, if nothing else it was good exercise in removing diodes from the donor boards. I added leaded solder as I removed them from the donor board, at least they cannot get away that easy, and I have them primed with leaded solder ready to reinstall. After a lot of tries I did get it into place. Would have been so cool if that would have done the trick, since there are lots of them on the old board in the audio circuits, but alas, no cigar. So I am back to zener diode shopping...Being in Canada makes buying stuff from Louis' website pretty expensive, shipping is over the top, for reasons beyond my comprehension.

    Leave a comment:


  • 2informaticos
    replied
    You can't solder it with iron tip.
    Use it only to place it on the flux, in it's place.
    Then use hot air to solder it.
    Microscope should help you a lot.
    Put more flux there, so hot air do not move it away...

    Leave a comment:


  • jurgenkoppen
    replied
    Yes, I was quite frustrated and had to call repeatedly on my infinite patience.Thank you for letting me know that I am not alone in finding this super tricky. The tiny bits either flick away or get stuck to the iron. I will educate myself , there must be some youtube channel that discusses how to go about this. I shall never surrender....if anyone else can do it, then so can I. Cheers, you are an awesome teacher

    Leave a comment:


  • 2informaticos
    replied
    First time I soldered D7012, I lost two; is a nightmare.
    You must put leaded solder on its pads first.

    Leave a comment:

thread bottom ad

Collapse
Working...
X