Released on September 19, 2014, this 5.5" screen iPhone is the larger version of the iPhone 6.

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Is this long screw damage? Seems brain dead

Hello all,

So I received an iP 6plus the other day. Client brought it in for screen issues to another shop.

It was powering on before he brough it to them, and after it was dead.

I spotted long screw damage - Excavated a bit but all the traces where I was expecting a break look good. What do you all think from these picture?

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Other than that - Looks like it had touch disease - Probably the screen issues he was having. Has a piece of rubber stuff stuck onto the chips to apply pressure and flux everywhere. I haven't poked around there yet to see if anything is off.

Looks like with my usb ampmeter - its pulling 0.9 then jumps between 0 and .9 over and over again during boot. No image on screen.

What do you all think?

*Update - original photo*

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did you plug it in to a bench supply to see if its drawing any amps before prompting to boot

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Have you tried plugging it into a computer to see if it's detecting it ?. If it's jumping around like that I'd check the lines that run under the screw hole for shorts / breaks using diode mode.

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@daniel , I am waiting for my squid still... I think today it should be here so I can do that!

@contact, no detection on the computer. Jumping around being more .9-0-.9-0 with the battery in - without battery, I get nothing when prompting to boot. I did check a few of the lines, my probes are kinda big, and I'm afraid if i sharpen them, ill tear a trace just trying to get on it.

I have a feeling that there is no long screw damage here. If anything, the top grounding plane was shorting to a line, but that has been removed. Yesterday, I took a quick peek at the backside of the board - and what a fun mess.... Can a touch IC issue cause no boot? (issue being bad contact - not a short)

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did you try it with a different battery and screen. sure let us know the outcome with the bench supply

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OK! Better late than never? @daniel So I finally got my power squid... Had to touch it up a bit as it was super cheap...

I am confirming power on VCC_Main and also - the power button is getting its proper voltage.

When hooked up to a bench, there is 0 current draw. After prompting to boot with power button - still nothing (below 0.00A if any) No warm spots obviously.

Just posted to boot by plugging in the lc. and what do you know... Meson is getting burring hot. Not much of a surprise there. Time to run me a M1 jumper and slap a new Meson on.

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If a previous tech tried to repair Touch Disease and didn't succeed, I would be concerned about excess heat spilling over to the CPU, bridges and shorts under and around the Touch IC's etc. I would start at the beginning and check all the PMIC/BBPMU power rails to see if there are some obvious issues at the subsystem level. I would also check the RESET_1V8_L line to see if it is oscillating as well.

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Hey @refectio, I finally got the needed supplies for testing and doing more for this board.

So, with a known good housing and on DC power, using the LC to prompt for boot, Meson is getting burning hot. Yes the PMIC is also getting warm, but that's normal for an issue like this. Correct? It has to feed the short also. Im going to pull off the Meson and run the M1 jumper + a "new" Meson. First time trying this batch. Hopefully no extra problem from heat... Would you still suggest checking all the PMIC and BBPMU power rails? After replacing this Meson, is it somewhat normal for there to be another problem that would take out the replacement? I guess the best would be to test rails for shorts after pulling and cleaning the pads.

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If you have a (partial) short, as suggested by the excess heat, it's always a good idea to check the PMIC rails. If the lower shields are off, then check BBPMU also. The M1 jumper being there or not should not cause excess heat on Meson. I would check the 5v7 and 5v1 lines that power the Touch IC's.

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The heat was from before the M1 jumper was run. Now all seem like normal operating temperature and also it is booting with no issues - except for no touch. I feel the next logical step would be Cumulus due to them messing up Meson. All the small componens looked ok, nothing nudged and when I removed the black stuff from around the fpcs on the otherside nothing came off with it.

When I'm back in my lab, I'll check out that 5v7 and 5v1. First thing though will be to stick my own screen on yo make sure I'm not getting trolled!

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@refectio Sorry for the long delay in the updates. So, 5v7 and 5v1 around the touch ICs check out ok. I went ahead and replaced Cumulus, but that didnt change anything. If my m1 jumper is not connected well or at all in this case, would i have a grey bar also?

So, I was doing some poking around, found a diode resistance measurement way high - pulled Meson again because it as on pin G2, and noticed there was a short between sage_to_cumulus_in<8> an <3> between c2419 and c2460... Cleared the short, reballed Meson, somehow the m1 jumper was still chilling where it should be after flattening the pads - installed everything and its working great now!

Woo Whoo! Time to invest in a real microscope instead of a usb one... I didnt even see that short the first few times working on meson.

Thanks for the help!

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Great work @joesipaq *pat on the back for you sir*

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Joseph Hughes will be eternally grateful.
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