Skip to main content

Repair information and guides for the iPhone 6 that was released on September 19, 2014. Model Numbers: A1549, A1586, and A1589

4994 Questions View all

Clue as to what went wrong here? iPhone DEAD after chassis replacement

Hi everyone,

I'm a bit stumped at the moment, and unsure how to proceed.

Background: attempted, what seemed, an uneventful screen + rear chassis replacement on my iPhone 6 (16GB, iOS 11.4.1). No prior issues with the phone/screen- just wanted to freshen things up a bit. Using iFixit guides, I first replaced the screen and tested the new screen in-situ (working just fine), then removed the new screen and carried on with a full chassis replacement- being mindful to disconnect the battery flex before attaching/detaching the screen cables. Wrapped up the repair & closed up the phone, but on attempting to power on; nothing happens- black screen/no startup sound/images...absolutely nothing.

Currently: followed the battery of troubleshooting tests suggested online:

  • care in avoiding long-screw injury (screws all initially labelled) on front panel assembly bracket ✓
  • double-checked all screen cables properly fitted & in the right place ✓
  • disconnected battery (then screen cables) & performed a power cycle ✓
  • plugged phone in to charge for ~1hr (no response- no battery symbol/sound/heat) ✓
  • disconnected battery & plugged phone directly into power source (no response, as above) ✓
  • plugged phone into Macbook (no response- not showing in iTunes or anywhere else) ✓
  • retested old screen (no response, as above) ✓
  • checked all other connections (scraped phone down to the bones again) ✓

It just appears completely unresponsive/dead. Just can't fathom what the issue could be?! I'm trying hard not to think that, somewhere along the line, despite being obsessively cautious and following the iFixit guide to a T, the logic board was inadvertently damaged- but I'm losing hope.

Questions:

[1] Does anyone have any idea what might actually be going on here?

[2] Any additional ideas for troubleshooting?

[3] Any definitive test(s) that could differentiate whether it's a logic board issue vs something else?

[4] Any suggestions/solutions based on what you think might be the likely cause?

[5] Finally, are there any users particularly versed in these sort of issues, that I can reach out to?

Thanks in advance for help guys! I'll be truly grateful.

Answered! View the answer I have this problem too

Is this a good question?

Score 1
Add a comment

1 Answer

Chosen Solution

First question: Did the replacement housing include flexes pre-installed or did you have to transfer them over?

It was smart of you to test the screen first. Unless something happened to it during the rest of the procedure, we can assume it is still in working condition (do a quick visual inspection of the flexes and connectors nonetheless).

As for the housing, if it was pre-populated with flexes, I would try the board in the original housing to see if that makes a difference. If you had to transfer the flexes, then inspect them closely for tears. Finally, do a thorough visual inspection of the logic board, preferably with magnification.

Now, the best way to help isolate the issue is to use a bare-bones approach. Connect just the battery and Dock to the logic board. Then connect to your Mac and see if the phone is recognized. If it is, then connect one flex at a time until the phone fails.

If the bare-bones setup is not recognized, you likely have a logic board issue. It could still be the battery or Dock but if there is no visible damage to the dock and you can measure the battery to insure it has some voltage present (preferably >3V), the phone should charge and/or boot. I would use the known-good dock from the initial housing if you have two versions of them.

A USB Ammeter is also useful because it will let you know if the board is drawing any current (even if not booting).

Was this answer helpful?

Score 5

4 Comments:

Hi Minho, thanks a lot for your detailed reply. Gonna have a crack at it now (long night!) & will report back once I'm done.

The replacement housing did indeed come with its own, pre-installed flexes (alongside: power/volume buttons, ringer, vibrator & charging port)

Before delving in, can I double-check a couple things you mentioned (1st time attempting any of this):

[1] By 'Dock', are you referring to the Lightning connector/port and its cable assembly? (i.e.) the bit that you plug the charger into?

[2] Using the bare-bones testing approach, isn't there the risk of damaging/blowing the logic board/its filters, by plugging-in each of those other flexes whilst the battery is connected?...as is the case with the screen flexes. Or is that risk unique to the screen flexes?

[3] Could the screen itself be damaged IF the battery wasn't disconnected whilst attaching the screen flexes, or is it usually the logic board/its filters that goes?

Thanks again for the help Minho! Will check-in again once I'm done.

by

1) Yes the dock is the Lightning/Headphone Port Flex

2) ALWAYS disconnect the battery before disconnecting/connecting any flexes.

3)Possible but usually it's the filters that blow.

Now that I know the replacement housing came with flexes, do all of your tests with the original housing as that is the last known-good state (unless you can see visible damage on some flexes).

by

Just chiming in again to say a massive THANK YOU to Minho!- spot on!

Only just managed to get back to the repair last night (long week at the hospital) and, after scrapping the phone down again & testing each flex at a time, eventually found the culprits: the preinstalled (i) Dock assembly flex cable + (ii) Power button flex cable, on the new chassis. Replaced them both with their older counterparts (from the old chassis), and the iPhone booted up with no issues.

For anyone finding themselves in a similar position, 2 things:

[1] Try Minho's suggestion, and be systematic in testing each flex, one at a time.

[2] Don't assume that all the preinstalled parts included in your 'new' housing are functional!

Can't thank you enough again Minho- really do appreciate all your help!

Best, UK_Medic

by

Always happy to help!

by

Add a comment

Add your answer

UK_Medic will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 1

Past 30 Days: 1

All Time: 108