Digitizers lift back off after replacement

I have replaced LCD/Digitizer assemblies on 4th gen iPod Touch's over 300 times in the past two years and it took a while to get it down to a science. If the glass was not shattered too badly to begin with, I use heat to carefully remove the glass and preserve the original adhesive, clean with alcohol and toothbrush when you are done picking out the shards, and be sure to keep track of which screws go in which positions. Install new screen and reassemble.

If I do the above method and still have that top left corner raising on its own, I disassemble the iPod and remove any extra thickness wherever I can.

1. Remove the foam/adhesive from beneath the WiFi antenna (it's still sticky after ^^)
2. Remove the bushing under the top screw of the volume keys
3. Remove the transparent 2-sided tape from beneath the metal plate that raises it off of the motherboard where the volume flex connects.
4. Remove the black tape on the top of the volume flex screws.
5. Ensure the metal casing is not dented on the back, and that the corners are not bent.
6. If they are, bend them back.
7. Last resort, blame the parts and super-glue it in place.

I only replace the adhesive if the existing stuff is full of glass fragments and dirt.

I had similar issues... I later discovered it could be one of three things:

1. Slightly warped screens (defective LCD digitizers) that won't sit flush no matter what you do.
2. Thicker LCD digitizers - Apple depth specification for LCD digitizers is between 2.95 mm - 3.00 mm. I measured several original digitizers with a micrometer, the max depth was 3 mm but most of the LCD digitizers available on eBay & Amazon are thicker than 3 mm.
3. The metal that holds the volume button (top-left hand corner covered in black) if not well secured after lifting the logic board will push against a thicker LCD digitizer thus the lift you see on the top-left hand corner.

With the issue you have described, it is more of #2 and #3. I hope this will help you with your repairs.

============================

Dan, Thanks a lot. I was able to completely disassemble the iPod. It was easy! And you're absolutely right about your original instructions - makes it possible to achieve a screen that sits flush. And thanks for GoUnlock.com - they have just about everything at reasonable prices plus videos! I really appreciate your input. You're the best!!!

Hi Robert,

I have replaced several digitizer/LCD-units and sometimes, but not always, I had the same problem.

I always check out if there is something stuck in the clamp holder of the metal clamp and if it really "snaps in". But it seems, that in your case, everything is clean and works.

I recently "switched" to super glue to avoid that metal clamp/bracket to get loose or to move, even slightly. It seems to me that the adhesive that I used was sometimes not strong enough to hold down the digitizer/LCD-unit permanently. With super glue, however, the problem seems to be solved. I would Just put a few dots on the back of the metal bracket and let it dry.

But there is one disadvantage: Once you use super glue, the metal plate can not be removed again in case of a (later) replacement of the digitizer/LCD-unit.

I hope I could help.

Steffen

Are you cleaning any old adhesive and glass from the wifi cable and surrounding area? Also, after you fit the new screen, I always heat up the screen adhesive areas to soften it, then clamp down the screen so it can cool and create a strong bond.

Are you transferring the metal bracket? I know its on the opposite side, but it seems to make the top area seal better.

Hope that helps.