iPhone 3GS repair - I need your advice!

[viperGTS]

Hey MacRumors. A while back I attempted to self-repair my iPhone 3GS myself (really i just wanted to get rid of the dust under the screen, i referred to a youtube video to do this), but unfortunately i got stuck with the dreaded white screen.

I was desperate to fix it, and i needed a working power button, which my 3GS lacked. So, i bought a replacement back housing (included the battery, new buttons, etc.) and successfully installed it!

So i tried a hard reset, holding power+home, but my 3GS STILL had the white screen! So i gave up for a while, and later i sent my phone in for a diagnostic.

My results? The logic board on the phone had malfunctioned.

I knew this was BS, because the phone is still recognized by iTunes, even to this day as i type out this post. I can still restore it, sync to it, charge it, pretty much do anything to it, except USE it because the screen is white. In fact, the phone even makes the charging sound when i plug it in to charge.

So MacRumors, i need YOUR advice.

Should I:
a. Abandon the phone and accept that it cant be repaired.
or
b. Get the phone to a repair shop to have the entire screen replaced.

?

What do you guys think? Should i listen to the advice given by the diagnostic i received, or go forth and pull the trigger on a new screen replacement?

Thanks!

[Greencardman]

It sounds like you damaged the display cable during your repair. In any event, I would attempt the repair again and see if its just a problem with the connection. Try the iFixit guide:
http://www.ifixit.com/Guide/Installi...Display/1542/1

I would carefully examine the part to make sure you haven't damaged it, especially the cables on the LCD. You may have damaged the connector on your logic board too, in which case the diagnostic would be correct. So I would examine that too and also clean off both connectors with isopropyl alcohol.

[Ibuyiphones]

- put the OEM battery back
- make sure the wires attached to the screen SNAP in good
- if this still does not fix it the LCD might have gone bad. Yes it does happen just like that.

[viperGTS]

Originally Posted by Greencardman

It sounds like you damaged the display cable during your repair. In any event, I would attempt the repair again and see if its just a problem with the connection. Try the iFixit guide:
http://www.ifixit.com/Guide/Installi...Display/1542/1

I would carefully examine the part to make sure you haven't damaged it, especially the cables on the LCD. You may have damaged the connector on your logic board too, in which case the diagnostic would be correct. So I would examine that too and also clean off both connectors with isopropyl alcohol.

I will try this. How will I know if its either the logic board or display cable though, and what exactly should I be looking for to make sure the logic board is/isn't damaged?
Thanks for your reply.

Originally Posted by Ibuyiphones

- put the OEM battery back
- make sure the wires attached to the screen SNAP in good
- if this still does not fix it the LCD might have gone bad. Yes it does happen just like that.

I'm not good with the battery replacement process. The battery works just fine too. Back then I reconnected the display several times, making sure it snapped in good but it still did not work. I will try again though. Thank you.

[Greencardman]

Originally Posted by viperGTS

I will try this. How will I know if its either the logic board or display cable though, and what exactly should I be looking for to make sure the logic board is/isn't damaged?

The display cable will fit into its connector on the logic board with lots of tiny pins or grooves. First, check to make sure the connector on the logic board isn't moving or loose. Then check to make sure it doesn't look damaged on its face, make sure none of the tiny grooves look pushed around or damaged, that sort of thing. Then check the other end to look for the same problems.

I would also make sure nothing has gotten inside any of the grooves, and then clean it up with isopropyl alcohol to make sure it isn't a dust, dirt or corrosion problem.

Then start following your cable back to the LCD, checking to see whether there is any damage, or if it got bent, ripped or kinked. That's about it for the LCD. If it still doesn't work after that, you may have either a bad LCD like someone said, or have a bad logic board. Maybe you damaged it somehow.

[viperGTS]

Originally Posted by Greencardman

The display cable will fit into its connector on the logic board with lots of tiny pins or grooves. First, check to make sure the connector on the logic board isn't moving or loose. Then check to make sure it doesn't look damaged on its face, make sure none of the tiny grooves look pushed around or damaged, that sort of thing. Then check the other end to look for the same problems.

I would also make sure nothing has gotten inside any of the grooves, and then clean it up with isopropyl alcohol to make sure it isn't a dust, dirt or corrosion problem.

Then start following your cable back to the LCD, checking to see whether there is any damage, or if it got bent, ripped or kinked. That's about it for the LCD. If it still doesn't work after that, you may have either a bad LCD like someone said, or have a bad logic board. Maybe you damaged it somehow.

Okay, I'm inside the phone. I took out the screen assembly and I'm currently looking at the connections.

EDIT: First thing I notice right off the bat is that all 3 ribbon cables naturally bend opposite the direction the display faces. Almost like an L shape with the display. IIRC these cables should not be bent at all, correct?

[Greencardman]

They should bend like the picture in Step 6 (You can click to make it larger).
http://www.ifixit.com/Guide/Installi...ssembly/2029/1
Basically they come out the top of the phone it looks like, and bend down to lay flat against the back of the LCD.
I don't think you can bend them the wrong direction, otherwise all your connectors would be upside down and your cables twisted too.

Edit: P.S. The LCD cable is #1

[viperGTS]

Originally Posted by Greencardman

The display cable will fit into its connector on the logic board with lots of tiny pins or grooves. First, check to make sure the connector on the logic board isn't moving or loose. Then check to make sure it doesn't look damaged on its face, make sure none of the tiny grooves look pushed around or damaged, that sort of thing. Then check the other end to look for the same problems.

I would also make sure nothing has gotten inside any of the grooves, and then clean it up with isopropyl alcohol to make sure it isn't a dust, dirt or corrosion problem.

Then start following your cable back to the LCD, checking to see whether there is any damage, or if it got bent, ripped or kinked. That's about it for the LCD. If it still doesn't work after that, you may have either a bad LCD like someone said, or have a bad logic board. Maybe you damaged it somehow.

Originally Posted by Greencardman

They should bend like the picture in Step 6 (You can click to make it larger).
http://www.ifixit.com/Guide/Installi...ssembly/2029/1
Basically they come out the top of the phone it looks like, and bend down to lay flat against the back of the LCD.
I don't think you can bend them the wrong direction, otherwise all your connectors would be upside down and your cables twisted too.

Mine don't bent like that. In fact, ribbon cable 3 has a permanent fold on it.
Should I post a picture of the display?

[AlphaDogg]

Originally Posted by viperGTS

Mine don't bent like that. In fact, ribbon cable 3 has a permanent fold on it.
Should I post a picture of the display?

Yes. A picture is worth 1000 words. I have a feeling that you just need a new LCD.

[Greencardman]

It looks like #3 should have a double bend, at least that's what it looks like from the photograph.

Nevermind, i just took my 3G apart, no double bend. They should all come out the phone at the top and bend back to lay flat against the back of the LCD. There is a free hanging loop of cable also there as well.

[viperGTS]

Alright, here are some pictures:


This one is of the areas on the logic board where the display connects.

[viperGTS]

This one is the display assembly as it comes out.

I'm not sure why it's upside down. Sorry.

[AlphaDogg]

Can you post a close up of the connectors on the display assembly?

[viperGTS]

Originally Posted by AlphaDogg

Can you post a close up of the connectors on the display assembly?

No problem.



This is about as close as I can get. Sorry. Pictures taken with a 4S

[AlphaDogg]

Originally Posted by viperGTS

No problem.

Attachment 388167

This is about as close as I can get. Sorry. Pictures taken with a 4S

Hmm I don't see anything wrong with any of them. Try connecting all of them, putting pressure on the LCD connection, and then turning it on (leaving the iPhone open and your finger pushing on the connector). If that works, it's almost certainly the motherboard.

[viperGTS]

Originally Posted by AlphaDogg

Hmm I don't see anything wrong with any of them. Try connecting all of them, putting pressure on the LCD connection, and then turning it on (leaving the iPhone open and your finger pushing on the connector). If that works, it's almost certainly the motherboard.

Weird... I'm doing this now and now the screen won't turn on at all. The phone still makes sounds though. I just heard the lock click. Unfortunately now when I rapidly press the power button the phone blinks a faded white. Has the phone died?

[AlphaDogg]

Originally Posted by viperGTS

Weird... I'm doing this now and now the screen won't turn on at all. The phone still makes sounds though. I just heard the lock click. Unfortunately now when I rapidly press the power button the phone blinks a faded white. Has the phone died?

Exactly how much pressure did you put on it?

[viperGTS]

Originally Posted by AlphaDogg

Exactly how much pressure did you put on it?

Quite a bit.

[AlphaDogg]

Originally Posted by viperGTS

Quite a bit.

I didn't mean to put a lot of pressure.. Just a little bit with your thumb. I think you damaged the socket on the motherboard.

[viperGTS]

Originally Posted by AlphaDogg

I didn't mean to put a lot of pressure.. Just a little bit with your thumb. I think you damaged the socket on the motherboard.

I hope not. but if that's the case, I'll just have to accept it... The motherboard seems fine though.

[AlphaDogg]

Originally Posted by viperGTS

I hope not. but if that's the case, I'll just have to accept it...

There's one more thing left to do before ruling it out as a motherboard issue. Take the LCD off of the screen assembly and inspect its ribbon cable. If there is any damage whatsoever, it's most likely to be the LCD. LCD's are pretty cheap for the iPhone 3GS nowadays.

[viperGTS]

Originally Posted by AlphaDogg

There's one more thing left to do before ruling it out as a motherboard issue. Take the LCD off of the screen assembly and inspect its ribbon cable. If there is any damage whatsoever, it's most likely to be the LCD. LCD's are pretty cheap for the iPhone 3GS nowadays.

So I would separate the glass and LCD? Can't I just check the ribbon cable associated with the LCD? I could barely put the entire display assembly together, I doubt I could add a new LCD.

[AlphaDogg]

Originally Posted by viperGTS

So I would separate the glass and LCD? Can't I just check the ribbon cable associated with the LCD? I could barely put the entire display assembly together, I doubt I could add a new LCD.

Yeah. Try this: http://www.ifixit.com/Guide/Installi...Display/1542/1