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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)
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).
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.
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.
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.
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?
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!
I had lost my number keys 1-9, so I removed the lower case, peeled back the protective tape from the keyboard ribbon cable connector, flipped up the ribbon cable retaining flap, pulled out the ribbon cable, cleaned out the keyboard connector socket from both sides with dust-off, wiped the ribbon leads with a screen cleaning cloth, sprayed the ribbon leads with the dust-off, put it all back together and everything is back to normal. I followed steps 1, 2, 24 and 25 from the battery replacement guide provided by ifixit: MacBook Pro 15" Retina Display Mid 2012 Battery Replacement
I am also having an issue with this, it takes 3 seconds(sometimes longer or less) for my mj7u keys to work on my MacBook Pro (Retina, 15-inch, Early 2013). I have cleaned the keyboard ribbon and it is not that. I have tried mouse keys, PRAM reset, NVRAM reset and clean install. I have replaced the battery recently and this began shortly after, There was spillage in the laptop when I got it, but this has not effected the laptop before and like I said the keys work intermittently. Any help would be greatly appreciated?
I have the same problem, first it was the zero key 0, which I think I spilled on, and then just recently 7, U, J, M and I didn’t spill on those but they just stopped working. The funny thing is that they do sense it when I press them, their junctions have changed. For M, it would hide whatever I am working on. When I press 7 a few times, “12345” would appear. This “IOUYIOqqwOeqwIOU” comes out when I press U key repeatedly. When I press J key repeatedly, “adfghsadfgsadfgsadfghs” comes out.
