2.3GHz, 2.6GHz, or 2.7GHz quad-core Intel Core i7 processor (Turbo Boost up to 3.7GHz) with 6MB shared L3 cache.

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some buttons not work

some buttons not work - 7 u j m

if i press 7 - sometimes on screen appear 12345

if i press u - appears other buttons etc

I replace keyboard on new - same problem.

if i attach USB keyboard - all buttons work ok...

Problem in MB?

(and yeap, i reset smc)

Answered! View the answer I have this problem too

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Seb -

Lets go back to the way the key switches work again as I explained a given lineup of keys carry a common line (X-Y). These lines then go into a chip called a AD converter (Analog to Digital). As it turns out this one chip also has a USB interface and some other logic to program it.

So in your case (and the others) the line that goes into the chip has become damaged (servicing the column 7, U, J, & M keys).

How? I can't say for sure, most of the time these kind of issues are related to spillage or damage to the the keyboards kapton circuit board ribbon connector to the keyboards logic.

Other possibilities can be something dropped across the keys breaking them or a swelled battery pressing the keyboard shorting it out.

The keyboards (top case) I end up replacing most of the time (90%) have had spill damage. Everything from coffee, soda, milk and cat pee.

Older systems that have had issues with the batteries swelling (effecting more keys).

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Did you replace the top case or just the keyboard alone?

It sounds like the keyboard ribbon cable connection is not correctly seated on the logic board or something there has been damaged. Can you take some good detailed pictures of the connection and post them.

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I replace only keyboard.

I reattach cable many times it's not work...

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Can you take some good hires pictures of the ribbon cable and the connector on the logic board so we can see what you have. Also, take a picture with the cable inserted as well.

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Known LB issue to me happens once in a while with MBPR at my repair shop. Check out at LB keyboard connector port. You will notice corrosion or kind of stuff most probably internal condensation impact due to moisture trapped at some point of time. User will never realize as liquid spill - understandable. If you have a magnify glass, you can use that to look into keeping it vertical (I assume you have taken apart). If you do not see anything, use 100% alcohol at the tip of a soft brush and try to clean the LB connector port to Keyboard. After cleaning, dry it with a blower (hair-drier works if you blow with cool air) and assemble the topcase w/h keyboard. See if it resolves. If not, change logic board. Because the connector port is failing at one line.

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I have literally the same problem. Exactly the same keys i mean. 7 ujm and also stuff like ;'.

Have you found a solution to your problem? 7ujm is all in 1 diagonal line, what's underneath it?

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The keyboard is laid out in a simple X - Y system, so a given lineup of keys (rows) have a common line to the input logic. So depending on what happened with your system the line to the logic has lost connection. Now the real question is what happened. Did you spill something into the keyboard or did you damage the keyboard ribbon cable?

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I didn't spill anything. I think the real question is how come there is a problem with the same exact keys on the same machine.

Also, another person with the same problem:

http://forums.macrumors.com/showthread.p...

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You can follow this IFIXIT guide on what it will take to even get to the keyboard and even when you do Apple only sells the uppercase frame (the batteries are glued in and need to be replaced as well) Upper case replacement and review the IFIXIT teardown Teardown. unless you've done a few of these I would let Apple fix it.

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I have the same problem, same exact keys. I went into work two weeks ago, and my perfectly cared for Pro simply started producing the errant keystrokes. It has been babied, no water, no dust that I am aware of. Went to Apple Store, recommended a replacement upper case for nearly 600 Euro.

I took the machine back to my flat, suffered a bike accident on the way; when I turned on the machine, it seems to work, but intermittently fails with the same keys. I know that this sounds unscientific, but the blow to the computer seemed to re-secure the connection or move what I presume to be dust particles from the connector. So, when it acts up, I simply take a fist to the area of the keyboard that doesn't work, and what do you know, it works!

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A very strange tale ;-} I don't recommend you take that path again as the next time you may end up making things worse.

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OK, so what did that tell us? If you're upto it I would take the logic board out and check the screws & rivets that hold the keyboard to the upper case. Did you find any missing or loose? Look around the dead key locations.

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I haven't done this yet, but I guess that I don't have much to lose. Really disappointing considering how much money I paid for this machine. It was taken care of with kid gloves. No water, no dust, no drops, just failure for no clear reason. Apple rep said that they do see this on occasion.

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I had the exact same issue. Mid 2012 15" Retina MBP.

I pulled the ribbon connector out of the socket and re-seated it. I then lost THREE columns of keys, (Below the 8 and 9 keys now).

I figured since I made it worse, maybe I could make it better.

I flipped up the retention tab on the connector and inspected the pins where it connects to the logic board. It looked like there was a little piece of dust or corrosion or something.. who knows, between a couple pins.

I dipped a toothbrush in some alcohol and lightly scrubbed at the pins, and got the foreign object to come clear. I then blasted air into the connector to dry it out and blow any dust away.

Re-seated the connector, and IT WORKS. So I'm typing this on my fixed MBP keyboard.

Worth a shot. If it's already &&^&@@, might as well try to fix it.

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A blast of can'ed air is what I use when I find the system is very dusty. As you found out it doesn't take much to mess up these tiny connectors.

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