Macintosh portable keyboard keys not working

[d3jsp]

On a M5126 with backlight. Have a column of keys not working at all: Q W E and I [ENTER] keys. The key and buttons themselves look fine. Does anyone know how to restore/repair these

 

[finkmac]

check the ribbon cables? check the keyboard traces?

 

[3lectr1cPPC]

Is the Portable keyboard mechanical or membrane? If it’s mechanical, you might just have some bad traces, as was the case with my Apple extended keyboard.

 

[stepleton]

In the Portable, the keyboard and mouse are interchangeable: you can swap their locations. Each one plugs into a large header connector over a ribbon cable. Open your Portable's case (carefully!) and swap the locations of your KB and mouse and see if the problem is the same. If it isn't, then the problem is likely on your mainboard (which is what I suspect you will find, probably due to capacitor goo). If the problem is the same, then it's probably the keyboard that's broken.