Have you solved your issue?
I've fixed about a dozen of these, the past few years (they've turned into an unprofitable hobby). There are a number of problems you can encounter after replacing your touchscreen/digitizer on an iPad mini or mini 2 (I haven't tried models 3 and 4 yet, and this does not apply to the full sized iPads).
Note: Always dry-fit the pieces before screwing and taping/gluing everything down. Always turn the power on and make sure everything works before closing up: power button, LCD, touchscreen, home button, volume buttons, sound, cameras, and, if you care, smart cover.
Also, keep all the broken parts until you've really completed the repair. There are bits and pieces on the touchscreen that you might not even notice until you find the replacement doesn't have everything.
Oh, and clean the old LCD well before closing up. You may be proud of your fix, but at some point you'll be really annoyed at that thumbprint or bit of lint under the touchscreen that you could have cleaned up but didn't because you were in a hurry to call it "done". Actually I find this the most tedious part of process, as you almost always see another smudge underneath the touchscreen after it's closed up.
If you paid relatively more ($30-50) for a touchscreen, it should have everything on it, ready to install.
If you got the really cheap ($9) touchscreen, you need to transfer several bits from the old to the new screen
- The camera alignment frame (use hair dryer heat to loosen)
- The home button assembly (frame, button, use hair dryer heat to loosen)
- The home button ribbon cable (unsolder it, don't peel or rip it off)
- The "IC cable", which solders to the new raw touchscreen cable (unsolder it)
- The cover magnets that grip a smart (or other) cover down (not to be confused with the smart cover sensors, which are on the button ribbon cable)
Always clean thoroughly and use new double stick adhesive on the button frame. There's nothing more frustrating than a home button that becomes loose or floats around after you've closed things up. I sometimes resort to superglue in addition to the double stick adhesives if they're stubborn.
Here are some other problems you may encounter:
iPad screen remains blank after repair
- Battery connector not snapped into place
- LCD connector not snapped into place
- LCD connector misaligned
- -- It is easy to misalign the LCD connector when it refuses to "snap" nicely into place. Retry it, and try to be more careful. If you end up damaging the connector on the LCD ribbon cable, it becomes nearly impossible to align it properly and you'll never feel that satisfying "snap" into place. I mainly saw this when I tried to reuse one LCD in several different iPads in order to test them. I wore out that connector.
- iPad Mini needs to be reset (power and home button pressed for 15 seconds)
- Backlight fuse has blown
- -- A symptom of the a backlight failure is that you can actually see the contents of the screen in a strong light (direct sun or a bright lamp).
- -- This can be caused by not unplugging the battery before unplugging the LCD.
- -- Sometimes it just happens. I've had the fuse blow when it's been closed up and in use for months.
- -- The "backlight fuse" is really a small inductor. It's difficult to reach and I usually just bridge across it with a fine wire rather than replace it. The "backlight IC" is just a large diode. It's even more difficult to reach and there isn't a quick and dirty fix, you have to replace it. I've only had to replace the backlight inductor once.
The screen shows the Apple Logo then goes blank -- Touchscreen not detected
- Ensure the touchscreen connector is attached
- If you removed a lot of tape to perform the repair, make sure it's put back, you especially don't want to short the IC cable pins to the case.
- If you performed soldering to the IC cable, double check your soldering job.
iPad touchscreen has dead regions
- Poorly soldered connections to the IC cable.
- --There are videos on youtube which show people soldering that IC cable with large, oversized soldering irons. They use lots of flux and clean irons. If your iron tip is rough, or you didn't use enough flux, or you had to solder over and over to get it right, you may have damaged the extremely fine traces on the ribbon cable. You need decent magnification (inspection microscope) to even see the damage. You'll have to get another touchscreen and start over.
- Damaged ribbon cable
- -- There are almost 70 signal traces in that ribbon cable. You can't tear it, then tape it or press it back down and expect it to work. There is no place on that cable where a tear is "safe". You can't replace it either. Get a new touchscreen.
- This one really sucks. If the touchscreen worked before you closed up the iPad mini, then stopped when you glued it down, you probably pinched the ribbon cable with a tight fold. If you remove the touchscreen without breaking it, you might be able to unpinch the cable and it'll come back to life, but most likely you've damaged the cable and you'll have to go get another touchscreen and start over. The last thing I do before closing up the touchscreen (I mean the very last thing, after the double -stick adhesive is in place and the camera-end is stuck down), is reach in with a pair of long tweezers, grab that touchscreen ribbon and "curl" or twist it so it doesn't get folded flat between the chassis and the screen.
Home button spurious activation
- This is another symptom of a pinched touchscreen cable. See above.
Home button doesn't work
Smart cover no longer detected
- Button ribbon cable not soldered well
- Touchscreen ribbon not soldered to IC cable well (there are 8 pins dedicated to the button and smart cover sensors on there)
- If you purchased pieces on-line and bought a button ribbon cable, you might have noticed that there were $2 cables and $10 cables. Guess what, the cheap cables are missing the SMT parts which make the smart cover work. Most people apparently don't check that, or don't have a smart cover, or were happy that the rest of the touchscreen now works, and didn't want to look into why the smart cover no longer works.
Oh, there are so many other things that can go wrong. An open iPad is a fragile thing. Once closed up, they're pretty robust.
I am currently wondering why an iPad mini on my workbench that booted last week, has run down its battery and chimes every 30 seconds when I try to charge it. The screen remains blank and it doesn't appear to boot. There's no Apple icon, and it's not the backlight. I haven't tried to reset it yet.