I came across this issue a few times in space and on Arkadia. If my ship is damaged so much I have to repair it, I found that I can not just select my tool and start repairing. I get an error saying that I must have the right tool equipped in order to do the repairs. But I have my Rk-5 equipped and have welding wire ready to go. What I found is that I have to actually right click on my vehicle and click "Use Tool" in order to start the repair process. Is this the proper way of doing it, or is it a bug. Just curious, thanks.
I have seen this bug before, if it's the same one. To fix I have moved right underneath the ship and then it works OK.
Same issue ... I had a veh down to zero structure and when I used the RK-5 to repair I get a message in the line of "veh too damaged for repair, need to use dedicated tool". A fellow soc mate came and started fixing it for me by using the "use tool" action icon, as I know my hotkey didn't work. jc