How can I find my problem? (Backlight)

Hello,

I was carrying out a screen repair for my little brothers MacBook and everything was running smoothly even had the backlight working and had it all on to make sure it was fine before reassembling.

When I turned it on I noticed an awful lot of heat coming from the right hand side of the Macbook and the backlight just switched off but the keyboard lights are still on, I then turned the Macbook off by holding down the power button.

I have turned it on and tried to shine a light through the back because I understand that if it is the backlight itself I should still see some of the screen but I am not even seeing any of the LCD working now.

I unscrewed the back panel and had a look at the small fuse but it's so tiny and I cant tell if it is blown as I don't have the required tools continuity meter.

Does anyone have any ideas as to what is could be? I did buy a cheaper version of the screen from ebay, so I'm now thinking it may be the actual screen itself as my understanding is that the 2 ribbon cables I actually connect into it turns the backlight on?

*Also can I just had I can smell a burning smell from the long pin on the screen and macbook side, like it has overheat.*

Thanks for the help in advance,

Jamie

Answered! View the answer I have this problem too

Is this a good question?

Score 0
Add a comment

1 Answer

Chosen Solution

Please could you add some pictures? For example, what do you mean by "long pin on the screen"? Have you replaced just the LCD panel or the whole lid assembly? Which 2 ribbon cables are you talking about, the backlight and LCD cable when replacing just the LCD? If so, it's possible you plugged the backlight cable in the wrong way.

If you cannot see any picture, this would not be a backlight issue. Try the original screen to see if it is showing picture, or lighting up, to determine whether it is a board issue. You may have chipped the LCD cable on the new screen, which can short the LCD connector on the board.

A cheaper version of the screen wouldn't cause an issue, all 11" LCD panels are original AUO, LG or Samsung, they don't produce copies (you likely got sold one where it does not have the original screen protectors, has been peeled off before, cleaned and reapplied).

If you do not have the multimeter to measure points on the board, or the tools to replace soldered components, I would recommend trying the original screen, and if it is a board issue, sending it somewhere. When carrying out logic board repairs, there is always a chance of making the issue worse if you don't know what you are doing.

I do not have a schematic or board view to hand for this model, but if you get hold of these and a multimeter, the first thing I would check is LCD_IG_PWR_EN, to see if it recognises the screen being plugged in.

Was this answer helpful?

Score 2

Comments:

Can I just say thanks Reece and sorry I wasn't clear enough on the question.

I replaced just the LCD and I wasn't thinking clearly enough I had the old popped one to hand. So I just reconnected that as you suggested and the backlight now works, what causes this?

My new screen from ebay now doesn't work at all, doesn't even allow the backlight to power up but my old popped screen does...

Oh well I guess I need to order a new screen, does anyone have any recommendations as I don't want the same to happen again, I paid £35 for that last screen.

Thanks again Reece you are a life saver!

by

Glad it's fine. It was possibly just a faulty screen, although I haven't seen a fault like this before. Did you possibly plug the cable into the new screen the wrong way before, at some point? This could have blown something on the screen PCB when the power was running though it (backlight brings 25V to power the screen, so would have sent it to the wrong place).

Not sure where the best place for a new screen is, since I order mine in bulk from China. I did used to use a supplier on eBay when I first started though, began with "TJ"? All Air screens come from the same place to be honest, just imported from China and slightly different grades, so just order and plug in a new screen to test.

by

Yes, I had the backlight ribbon cable, the small thinner one with the pins facing up rather than down the first time I plugged it in and powered it on. I then corrected my mistake and the screen and backlight worked fine then, but after like a minute it just shut off and no life in it at all, but the old popped screens lights up like normal.

Thanks again, I will just order from the same place then and put it down to my own mistake with the ribbon cable. It was a one off repair but have learnt from it for sure, just glad no fuses are blown as I seen they are a pain to solder!

by

Add a comment

Add your answer

Jamie Watson will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 0

Past 30 Days: 5

All Time: 46