Customer said before it was working but just no service (network). Then he sent to previous shop, the guy restored the software and it ended with error 4013. Then it stuck at Recovery mode.
|Older iOS will display different iTunes logo and Cable.|
By hearing the client said it was No Service. We already know it got network or signal issue.
it's famous problem for iPhone 7 or iPhone 7 Plus. Same like iPhone 6 Plus touch disease.
This we called it - iPhone 7 Baseband disease.
OK, for who googled about this issue and found this page. I'm going to share some tips here.
I'm telling you that do not restore your iPhone. It was never a software issue. Definitely is HARDWARE problem.
If you insist to restore it, then your iPhone will stuck in Recovery Mode. So what so bad about it? Can't gaming or use app? No!! The biggest problem is some shop they intend to swap your expensive part like camera with faulty one.. since your iPhone unable to enter iOS, how you going to check all the function..
Mostly they don't have the skill to repair logicboard ic. So they swap those "plug and play stuff" and might charge you a diagnosis fee which they only attempt software method that restore your device in iTunes. This type of repairer with no skill usually gain more profit by doing monkey trick.
We are board repairer. Saw this kind of case a lot. The worst part is they created mess up failed repair. Causing us more work to repair it back. Might be more cost to repair when we found out some parts are not working after we managed repair the board to turn on.
So i strongly suggest you to keep the iPhone in a status which still can turn on and test all function/features.
By the way.... we have few ways to check it.
How to confirm it is Baseband problem:
- If you haven't restore yet, go to phone menu. Press *#06#. It will show your iPhone IMEI.
Nothing appear after you press *#06#, then it's confirm you having Baseband problem.
- Try dial 112. Baseband problem will just show you call failed (it's emergency call number which must be able to call out in most country, even for a locked iPhone)
- Error 1 or -1 in iTunes restored failed. (Only iPhone 6, 6P and older models)
- Error 4013 (iPhone 6S, 6SP, 7, 7SP) After fail restored, you still see iTunes logo in your iPhone. If it's no display and blank screen, then you having bigger problem which is out of today topic.
|Press *#06# then it show IMEI when the baseband CPU working|
Let's talk about how to repair it and why it happened.
First, i show you a photo on below. It's iPhone 7 which we removed the shield on top of the logicboard. We can see the Apple logo chipset with text A10. It's the main CPU of iPhone 7.
The red circle IC is Baseband CPU. (It's job is to control all the signal or cellular network) This is the guy.
|There are two type iPhone 7 / 7P.. One of it is using Qualcomm Baseband. The other one is Intel.|
Both are famous chipset maker. Which one better? I can't say. But i do have a statistic know which one failed most.
Why the problem happened?
A: It's because you dropped it too hard.
WHY? My other iPhone don't have this kind of issue even if i drop it thousand of times
A: This i can tell you. It is the Design flaw.
Because the baseband IC is sitting middle of the logicboard. In very center. So when the iPhone7 fell hard on the floor, the long logicboard will get little bend in midddle and return to position since this PCB is a bit flexible.
By so many black glue bounding between the PCB and this IC, the joint of this IC will still get cracked or lost contact.
So how to fix it?
A: Most of the case, it just need a reball the Baseband CPU with a better solder paste which is more durable than Apple. Some case might even need repair broken tracks between this IC to other line.
We don't know until we pull this BB CPU off.
To do this job, the technician himself MUST BE very skillful and experience. Master of heat control.
Why? Because CPU is SITTING next to it!! If you put too much heat, A10 CPU beside will short or died. CPU's hundreds of solder balls will be mess up with underfilled black glue.
|Reball done. Put all the capacitors and Inductor back.|
After all the technical skill works done. We must need to restore again.
|When the white bar is passed 50%. And iTunes doing second time of verifying iPhone restore. The problem is fixed.|
|YAY~ This is the message we love to see!!|
Tips: Always backup your data in iTunes. Even your iPhone has no problem.