Vertical black bar on iPad Mini 1st gen, tried 3 different LCD

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iPad Mini Wi-Fi

7,9 Zoll Display / Modell A1432 / Verfügbar in schwarz und weiß / Angekündigt am 23. Oktober 2012 / 16, 32 oder 64 GB Speicherkapazität

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JPL @jlapointe23

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Vertical black bar on iPad Mini 1st gen, tried 3 different LCD

Hello,

I am currently replacing a iPad Mini 1st gen digitizer and I noticed the LCD had a large vertical black bar. I tried 2 other LCD to see if the problem was still there and it is. Someone told me there might be filters to replace on the motherboard, is it possible? If so, which one would I need to replace?

I got ZXW so if you got the exact part number to replace I can look it up on there.

Thank you.

Here is a picture for reference: http://imgur.com/eaSAgXc

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Minho @refectio

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This problem does not have anything to do with the "filters" (in this case L2200 & L2201) IMO. The backlight works, the LCD is being driven...and you have tried 3 different LCD's. Do they exhibit the exact same problem or just problematic in general?

The LCD image is directly driven by the CPU and goes directly to the logic embedded in the LCD. Other than some common mode chokes (L2222 etc. - there are 5) in between the two, there isn't much there. I would check the connectors on the logic board to be certain they are not cracked or damaged. I would also test the chokes to be certain they are letting the data stream through. If you had access to a known-good LCD or another mini to verify those you have, then you could start eliminating some variables.

Let me know what you find, it might give me some other ideas.

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Thanks for your input. The 3 LCD's are doing roughly the same thing: black bar, not exactly the same position on the screen but very similar.

I already checked the connector and it is in perfect condition. I will look at the chokes to see if they are OK.

Feel free to add anything if you get an idea.

Thank you.

1. Sep 2017 von JPL

Let me know what you find.

1. Sep 2017 von Minho

Here is a picture of the iPad Mini motherboard if it can help.

Picture: https://imgur.com/bQooYeW

The chokes seem to be OK from what I see.

1. Sep 2017 von JPL

Okay, I took the resistance of each choke.

L2202: 3.3 megaohms

L2212: 2.8 megaohms

L2222: 2.8 megaohms

L2232: 2.8 megaohms

L2233: 2.8 megaohms

I guess the one that differ from the others is probably the faulty one?

1. Sep 2017 von JPL

How are you measuring the chokes?

Between pins 1&4 or 2&3, it should be low resistance (it's just a winding). Between pins 1&2 or 3&4, it should be a very high resistance (such as what you are reading.

Not sure if the difference between 2.8 MOhms and 3.3 MOhms should make a difference. However, considering that choke (L2202) is responsible for the clock signal, it may be the solution. These are pretty common chokes. you can get them at Digikey or harvest one from an iPhone 6 (L2044 - it has a higher current rating but should work) or check other schematics.

1. Sep 2017 von Minho

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Thanks for your input. The 3 LCD's are doing roughly the same thing: black bar, not exactly the same position on the screen but very similar.

I already checked the connector and it is in perfect condition. I will look at the chokes to see if they are OK.

Feel free to add anything if you get an idea.

Thank you. — JPL
Here is a picture of the iPad Mini motherboard if it can help.

Picture: https://imgur.com/bQooYeW

The chokes seem to be OK from what I see. — JPL
Okay, I took the resistance of each choke.

L2202: 3.3 megaohms

L2212: 2.8 megaohms

L2222: 2.8 megaohms

L2232: 2.8 megaohms

L2233: 2.8 megaohms

I guess the one that differ from the others is probably the faulty one? — JPL
How are you measuring the chokes?

Between pins 1&4 or 2&3, it should be low resistance (it's just a winding). Between pins 1&2 or 3&4, it should be a very high resistance (such as what you are reading.

Not sure if the difference between 2.8 MOhms and 3.3 MOhms should make a difference. However, considering that choke (L2202) is responsible for the clock signal, it may be the solution. These are pretty common chokes. you can get them at Digikey or harvest one from an iPhone 6 (L2044 - it has a higher current rating but should work) or check other schematics. — Minho

iPad Mini Wi-Fi

Vertical black bar on iPad Mini 1st gen, tried 3 different LCD

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