Keyboard and Power Button Problems

[velvet jones]

A couple of weeks ago, I turned around to notice that my 2-year old had pried two of the arrow keys from my 2009 Macbook Pro 13" keyboard. I tried to replace them, but in doing so, tore off the little silicone nipples under the keys, rendering them useless. However, the keyboard was functioning normally other than the two keys that were missing.

I've done quite a bit of hardware repair in the past, so I attempted to replace the keyboard. When I did so, the Macbook Pro failed to turn on at all. I tried to use the power button, and tried to short the pins on the motherboard--neither solution worked. I put in the old keyboard, and it worked once more--however, a row of keys (V, F, R, 4) had ceased to function. However, the power button was once again functional. I assumed that this was because the keyboard was bent slightly as it was removed originally.

So, I set out to replace the entire top case, including a new keyboard. However, with the new topcase and keyboard I'm having the same issue with the row of keys--they do not work--and the power button has again ceased to function.

Being clever, I left the *new* keyboard and topcase in the system, but removed its ribbon cable from the logic board. I replaced it with the old keyboard, and the power button on that one worked just fine, and booted the Macbook up. I then removed the old keyboard's ribbon cable, plugged in the new one from the new top case, and let the Macbook continue booting.

After boot, the new keyboard functioned--but the row of letters still did not work, and the power button still did not function. The computer is still on, and working--but I cannot use the power button at all, which means I can't actually shut this thing off and turn it back on again.

Any ideas on what might be causing this, and how I might repair it? Do I need a new logic board? Everything else is functioning normally.

Here's the TL;DR version:

Old keyboard before replacement: Fully functional with missing arrow keys
First new keyboard after replacement: Inoperable
Replacing new keyboard with old keyboard: Power button functional, keys VFR4 not functional;
Replacing old keyboard with second new keyboard: Power button not functional, keys VFR4 not functional

 

[Kaveman]

Are the parts from exactly the same model, some of the changes were ver slight and could account for what you are seeing.

 

[velvet jones]

Are the parts from exactly the same model, some of the changes were ver slight and could account for what you are seeing.

They should be, as far as I can tell. My MBP is a mid-2009 13". The last 3 digits of the serial are 66D, indicating that it's an A1278.

I purchased both keyboards (the standalone keyboard and the keyboard with topcase) from ebay:

http://www.ebay.com/itm/221054779255?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

http://www.ebay.com/itm/261128992322?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

The original keyboard that I replaced exhibits the same symptoms as the two I purchased from ebay, except its power button is functional (keys vfr4 do not function). On two replacements, keys vfr4 do not function AND the power button does not function.

I'm considering purchasing a new logic board, but I'm hoping there's something else I screwed up that I can fix.

 

[Kaveman]

Have you plugged in an external Keyboard and confirmed its a Keyboard Problem?

 

[velvet jones]

Have you plugged in an external Keyboard and confirmed its a Keyboard Problem?

Yes. I am currently using an apple Bluetooth keyboard d it functions correctly.