3 New Keyboard 10 keys Not Working
Hi all, I have an A1502 which had a minor spillage on the keyboard that I’m trying to repair. I’ve gone through the whole rivets pain and replaced the keyboard but found myself without a left Shift, Control and Option buttons.
Having seen a little corrosion on the keyboard connector, I found a great deal on a replacement logic board; once I did that, with the machine still open, I tested the keyboard and everything was working perfectly. Yet once I close everything up not only the Shift,, Ctrl, Option keys weren’t working again, but also the Z to M row.
I then got a new trackpad ribbon cable as I’ve read that it can cause those type of keyboard issues and with that nothing changed, same problem. Then I tested a new trackpad itself since the ribbon cable plugs into that at the other end, still same problem.
I had the new keyboard working at one testing stage, I have no ideas what to do now. Could it have broken during reassembly?
Any thoughts
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After a few more hours I have now actually confirmed that this is a software issue. Here’s the kicker though:
- OLD Logic board - the first 3 pins responsible for the left Shift-Control-Option are definitely corroded. So after the SMC reset I was able to get my Z to M row back
- NEW Logic board - I can’t perform the same SMC reset because the power button is not recognised as well as the mentioned keys currently affected
So right now I’ve disconnected the battery and I’m going to wait until the capacitor discharges hoping that it acts as a “forced SMC reset”
I’m contemplating keeping the old logic board and not care about the 3 left keys, but let’s facing, that’s a bugging thing to live with
由 Massimo 完成的
@maxnix76 - I can't see how this would be a software issue. The keyboard encoder chip is part of the main logic board not the keyboard its' self. The I/O expander / Keyboard Interface chips U4820 & U4830 which does have firmware loaded within it. So the replacement logic board is defective.
So going back to your current logic board which you state has corrosion damage on the connector, I would just replace the connector Keyboard Connector (30-pin)
由 Dan 完成的
Hi Dan, many thanks for posting a comment (I very much appreciate all the help). I came to the conclusion of software issue simply because every time I leave the machine with no power and no battery for while, I get a different result in which keys work without disconnecting/connecting any of the cables. But I may be totally wrong of course.
I have a 2nd new keyboard coming today to test that too since it's the only thing left to test. !&&*, I have 2 of each component HAHAHHAHA I surely must be able to find out what the heck is going on right?
But your suggestion that the replacement logic board could be broken as well throws a solid stress inducing scenario now.
Thanks for the link to the keyboard connector pin but I have zero experience on that type of work (I envy you guys that are masters at that type of repairs).
由 Massimo 完成的
@maxnix76 - Do you have anyone with micro-soldering skills local to you? I don't see how replacing the keyboard alone will fix anything. Did you damage the ribbon cable - Torn?
Both your current and new logic board have issues from what you've stated.
I just hate seeing someone digging deeper into a hole that doesn't have a way out and ends up being more expensive than it needed to be. Where are you located country & nearest city? Maybe we can aim you to someone who can help you.
由 Dan 完成的