"So, how much do you think a brand new iPad mini 2 retina version would cost?" wondered Wesley, as he faced the worst case scenario of any repair shop---having to buy a customer a new device because of a mistake someone made in the shop.
He had sent in an iPad mini to us for what he was hoping would be a routine backlight repair, not expecting to hear the words "catastrophic damage" as I updated him after looking at the board under the microscope.
Where had he gone wrong? Let's take a little quiz to find out.
Here is a similar iPad mini original version. We are about to screw on the connector area shield cover.
Which screws should we use?
A.) Any from the green group
B.) The yellow group
C.) The red group
D.) The blue group
In practice, many folks that haven't done a ton of mini's will go with A---it is clear that the yellow group screws are a little longer and go in the main LCD shield, but it doesn't look like there is a difference between the blue and red group.
But, of course, there is. A teeny tiny 0.5 mm difference. And that difference makes all the difference. C. (Always pick c) The red group is the answer.
If you've mixed together your three oh-ever-so-slightly-shorter screws from the connector shield with the many similar screws from the LCD shield then you are likely to grab the wrong one when you go to screw on the small connector. When you snug that screw up with one final twist of the screwdriver, all of the sudden the screw is loose again....wha??? Well, let's skip that one and at least get the thing stuck down with one of the other two screws. Better make sure its tight you think, but then again you're spinning that screw like it is attached to nothing. Because you've popped the screw bracket right off the board by over-tightening a too-long screw.
On the iPad mini original, this is a common lesson learned the hard way by all of us. Most usually figure it out by the 3rd screw---dozens of mini boards come through our shop that have the telltale missing one or two screw brackets for the connector shield. In the iPad mini original, this is one of the more forgiving mistakes to make--the entire connector shield is fairly superfluous.
But what about the mini 2? Well, from Wesley's point of view, this is where screw size gets serious. His story may just be anecdotal, but then again, it may just be one of the first of many. Here is what we found when his mini 2 arrived for repair.
Ouch. The entire top layer of the PCB has been torn off along with the screw brackets. Most of this is probably just copper ground, but there were at least some traces in there that have been destroyed. Repairing it would depend on building 'overland' routes of custom microjumpers to connect up stranded components with the rest of their platoons. It would be painstaking work with the schematic, but without it.....well, who wants to buy Wesley a beer?
The take home lesson is that when it comes to the iPad mini screws, size does matter. The next time you see all the screws mixed together, make sure your repair starts with a hunt for the three smallest screws for the little shield. Find them, and you won't get screwed.