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Corroded PCB path

Fixed with copper wire and electrical tape

I have a pretty old HCL Diamond keyboard with Cherry MX Black switches. It worked fine except for the keys Esc, F4 and F6.

After disassembling it, I took a closer look at the PCB. There was corrosion at the end of one path and the 3 keys were connected in that same path. I applied isopropyl alcohol and used a flathead screwdriver to scape off the corrosion, exposing metallic contacts.

Then I snipped off a single strand of copper wire from a electrical cable and used it to complete the circuit. I confirmed that the switches are still working if I touch their pins using a pair of tweezers. I don't need to de-solder and replace the switches now.

I used electrical tape to keep the wire fixed and padded with paper to keep pressure on the tape (since this side will always face downwards).

Total time spent: about 30 minutes.
Total cost: None as I already had the supplies with me.