GSM iPad 2 with 16, 32, or 64 GB of storage, and a Dual Core A5 Processor. Model Number A1396. Repair is complicated and requires heat and prying.

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Is this Backlight diode showing the correct reading?

I recently purchased this Ipad 2 A1396 as I was certain I could get it working again. With little experience behind testing filters and fuses I wanted this to be a learning experience.

The main issue is that the backlight is not on, causing the screen to display dim. So before I go out and shell out the extra money on an LCD that may possibly or may not fix the issue, I'd like to start with testing the circuit. As far as the research shows it's that the coil or filter are the usual suspects.

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So I pulled out the handy multimeter and test the coil first. Looks good to me as the circuit completed with a long beep. Now when I test the filter/fuse I get no beep at all. Before I go ahead and replace. Is there anything else I should check for? Or do you know of a way to bypass this and should I?

Also thank you for all your previous help.

Answered! View the answer I have this problem too

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UPDATE: Ok, so I ran a check on the diode using the diode (which I named filter/fuse because I'm dumb as !&&*) check feature on the multimeter and I got 0.732 which I would suspect is in working operation. With the coil and diode all showing good I'm stuck at crossroad here...

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UPDATE 2: To avoid any confusion on the diode, it's not reading 0.732 it's actually reading 0.143. Sorry.

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With that said, there's really nothing on the schematic that can really point me to if it is the correct reading or not. Maybe I'm just not looking hard enough. I'll update if I find anything.

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Honestly I'm still learning the ropes with the multimeter. I haven't given up on wanting to learn. I can cut wires, make jumpers, test resisters, understand polarities, but testing diodes and filters, and capacitors are something I've yet to learn. As far as what I looked up on the web for the diode it was that my multimeter had a Diode test function withe symbol -->|. So pretty much all I did was test both leads and got that number. I must be doing something wrong then.

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Ok so I've tested the currency of the resistors near the LCD connector and those all show ok. The diode shows 0.156 on and when switching directions I get nothing...nada. So I suspect the culprit to this whole thing is possibly this diode.

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I did get this working after replacing one of the faulty resistors. Thank you all.

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I wish I had an answer for you but those backlight issues on ipads have always been a nuisance. Have you checked out http://www.cyberdocllc.com/ before? I found them searching for information on this topic in the past and emailed them for help. Even if you do not use their service, they may be willing to help you troubleshoot it since we are all one big repair family :)

Best of luck to you and godspeed.

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Thank you Eric. I hope they can help. It's almost like most communities gave up on this issue, the more I research on it.

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Justin--this is an easy problem, very solvable.

1.) a hard reset will cure many backlight problems in the iPad 2--I'm sure you've tried that

2.) it is never the coil, I swear I'm going to put that on a T-shirt!

3.) it is always the filter, and sometimes also the diode.

Your filter is located under that EMI shield bracket near the diode. The filter is the small component that looks black--I'm on a phone so I can't label it for you. If it is burned you can see visual damage. You'll need to replace the filter. If you're not a microsolderer then send the board to someone like me or Marcus's (cyberdoc) new technician since he's not doing repair anymore, or any of the eBay folks. It is very straightforward.

Now measure your diode. Set your multimeter to diode testing and put the black lead on one leg of the diode, red lead on the other--should get a reading of 1 or 150-180. Switch leads and take second reading. If you have a 1 in both directions diode is bad, otherwise diode is good (usually it is good)

With a new filter, good diode and good coil--the only variables left are the lcd connector and the lcd itself

Jessa

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>>Hi Jessa,

Absolutely have tried the Hard Rest. :) I also would buy that "It's never the Coil" T-shirt. So I did manage to test the resistors next to the LED cable and they all look perfect. Next was the diode and I checked one end showing 153 and the other? nada. Sounds like it's working then as you mentioned. Next I checked the filter (which showed no signs of damage or burns) everything checked out with that. So in this case I checked the LED cable and saw no signs of damage, I went as far as running a continuity check on each pin also. Looks good. So at this point I really suspect the LED Screen is the problem and will need the replacement. I'll provide more updates once I have replaced this.

Thank you all for your continued and awesome assistance! You gents/gals rock!

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Sounds like you're on the right track. Some vendors have fantastic return policies so you can try it without installing it just to confirm, stay away from eBay and Amazon sellers.

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Any recommendations on a good reputable vendor? Cause you stopped from an Ebay purchase not even a 10 minutes ago after reading this.

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Actually answered my own questioned after a peek at the prices here on ifixit. So far I like what I see. Are there any quirks I should know about B-stock items that I should know? The LCD is really not a bad price at all at $49.95 w/ a 6 month warrantee. Seriously considering buying it here at the moment.

iPad 2 LCD

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I've never tried B stock, you'll have to let us know how it works out.

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Justin Aka Taco will be eternally grateful.
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