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820-4924-A no backlight
- Thread starter Davis
- Start date
Damn it! off course its not pin 2 it is pin 17 (the secound in that row
) yes i tested with 2 different screens for the same model/year.yes there is image, and yes u7700 pin 17 THE FUSE is fine also replaced it for any case..guess replacing Q7700 is next step.
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why is the SMC_LID measurments supprise you? did checked with KG displays.
Ok good il check that.
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ok so SMC_LID is 3.385 and not as I said before, got some wrong measurements before for some reason..no liquid or other damage on TP and cable.
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duke you seems like a quick guy but If you didn't noticed it yet I am a newbie to the board repair and that is the reason I pay a subscription on this site actually to get better, but if you can't handle this il pay another one to help me with my oops..remember your oops as a newbie or close this forum.
Rule #3 is proficiency with a multimeter.
This is a serious, and probably the most important rule. We are trying to help you without being in front of the board you are working on. The only way this is possible is if we receive accurate measurements from you. The advice we give you on what to replace, or what to do, directly correlates to whether you tell us 3.42v or 1.5v on a given line. There is no compromise here: newbie or not, basic multimeter proficiency is an absolute requirement before someone can do any type of component level board diagjosis or repair.
For example: a medical student may be a newbie to brain surgery, but it wouldn't be unreasonable to expect that they understand how to use a scalpel or administer general anesthetic. These two basic skillsets must be mastered before one can commence learning or taking part in brain surgery. The same way that, while you may be a newbie to component level board repair, we don't find it unreasonable that you be able to interpret & provide accurate multimeter measurements.
If any of these rules are a dealkiller, we will not close the forum, but highly suggest you unsubscribe. I don't mean this to be mean - but there's no one out there who is going to provide proper help if they can't make the reasonable demand of you that you provide accurate measurements for them to work with. We are upfront with the rules of this forum that while we are happy to provide you with a wealth of diagnostic troubleshooting advice, it must be based on solid measurements.
When SMC_LID is 3.42v, it thinks the screen is open. When SMC_LID is below 3v, it thinks the screen is closed, which points to a bad sleep sensor, or corrosion under the SMC. When SMC_LID is 3.42v, it points to a problem with the backlight circuit. We're going to tell you to do very different things based on the voltage you read on SMC_LID, so it is imperative that this be correct!
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It was all about the attitude if the measurements was wrong one could think it is because the lid was close which it probably was so just ask the right questions instead of rolling eyes on those newbies, I know where it comes from since I advice newbies in other levels, find the patience and ask the right questions thats all Im asking for.
Ok please lets proceed to the case.
I now replaced U7700, R7700, Q7700, F7700, Q7701, D7710, R7733, C7740, R7744 AND LVDS connector and yes tested with other displays but still no backlight!
try to guide me out Im probably missing something basic..
Ok please lets proceed to the case.
I now replaced U7700, R7700, Q7700, F7700, Q7701, D7710, R7733, C7740, R7744 AND LVDS connector and yes tested with other displays but still no backlight!
try to guide me out Im probably missing something basic..
15+16 continuity is good though I'm not sure about the pull up resistors, can you send me the part number on the .brd?