I am working on restoration of my flooded 17-55 lens and found out sth that I believe is really strange. I traced down all 10 F-mount connector pins to the CPU - all except one which is pin nr 2. This pin is supposed to be a handshake (or R/W) pin which as I know is mandatory for proper lens serial communication. However, it seems to be not connected anywhere. As you can see at the attached picture I removed the slot to see what is hidden underneath and nothing is there - pin 2 is literally not connected, at least in the top PCB layer, but there is no via holes on it too... I also checked it under microscope.
So my question is the following: is it possible for lens to communicate properly without this line connected or not? Unfortunately I cannot test it yet because I am still waiting for the reballing stencil for main controller... All suggestions are will be very appreciated.