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3 Sleep/Wake Button Doesn't turn off phone - Liquid Damage
My friend's iphone 3gs was dropped into a glass of juice due to a vibrating alarm.
It has the basic hallmarks of other liquid-damaged phones: no backlight, otherwise functional, except for the sleep/wake power button.
Thanks to the guides here on ifixit, I've taken the phone down to the rear-chassis, replaced the screen with a new one purchased here (to support the great service provided), taken the physical button out and checked for damage, looked at the circuits and connectors, and I still have the same problems.
So two issues, then:
1) Power button - The button clicks and physically appears functional. The headphone jack, volume up and down, and mute selector switch all work great. It doesn't seem that I would need to purchase a new ribbon cable/circuit of all those if just the sleep/wake functionality is not working. Anyone have a more detailed pinout of this circuit? Also, I saw something online where someone suggested loosening the screws holding the ribbon cable in, but didn't see that it was listed as an accepted solution.
2)No Backlight - despite a thorough cleaning with a toothbrush and 91% rubbing alcohol, and replacement with a new screen, I still don't have the backlight working. I've purchased the 6r8 coil listed in a lot of online discussions about this problem, and am ready to work on replacing that on the logic board itself if I can't resolve it otherwise.
It's possible that the connectors for these circuits have some damaged pins from the water damage and cleaning. (either the male or female connector.) The display suffered a lot of damage while vibrating in the juice. the solder on the logic board connector was gone on 3 leads, and one lead was bent over to another leads trace. I was able to repair that with the help of a scope, but I'm now back to square one. I'll do a more thorough cleaning and inspection of the connectors soon, but if you have any ideas, please share
Is this a good question?
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2 Comments
NOTE - I've resolved the power button issue by cleaning the contacts on both the logic board connector and ribbon cable.
Still have the no backlight problem. Testing the new coil and the old coil indicates same resistance, so I don't think the coil is the problem.
by repairthat
Don't know if I should start a new question or just update, so Mods, please feel free to let me know.
I've removed the display connector (connector 1) from the logic board, and discovered that one of the pads is 2/3rds broken (see pic taken with microscope.)
I want to attempt to repair it, and am wondering if I can use some adhesive copper foil that I found on ebay which is listed as conductive, but seems to be made for guitar shielding. http://cgi.ebay.com/Guitar-Copper-Super-...
I've seen some guides to pcb pad repair, and think I can handle it, but need to find cheap materials, rather than the several hundred dollars for a repair kit that I've seen online. I'm not sure if this copper would work. Ideas?
If I can't, I'll attempt to trace the circuit and jump/bridge the wire to the next point on the circuit.
Advice appreciated.
by repairthat