I've a broken remote for a cable TV box. It's been replaced,
so the repair is non-critical -- just-for-fun!

Anyway, 3-buttons failed simultaneously. They are horizontally
adjacent.

After disassembling and inspecting -- there seem to be no
broken PCB traces and the PCB contact portion of the keyboard
looks OK.

The key contacts are a thickish, black material applied to a
single-sided PCB in an open matrix pattern.

After some simple tests, verifying the "rubber" buttons for the
failed keys work at other PCB pads and that the "bad" PCB pads
weren't activated by "good" rubber buttons, there seem to be 2
possible (likely) failures:

1. A key-matrix leg of the control electronics has "died".
2. The "paint-trace" contact material has disconnected from
its PCB trace.

If the chip's died or a surface-mount element's fried, it's
probably not fixable. (Not by me anyway.)

So -- any suggestions on methods to re-attach the 3-key leg?

Or -- any other failure scenarios?

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