50's Seeburg Pinbank Selector Question

I started s l o w l y cleaning the 100 contacts, gently using an ultrasonic cleaning for all 5 centipede plates, followed by an eraser, all contacts now look shiny new. I noticed that 4 out of the 5 spring loaded contact plates had a thin Black cloth wrapped wire that had either broken off or fell off the side of the contact plates due to a cold solder joint.

I resoldered the Black wires back onto the plates, so all 5 silver plated contact plates are now reconnected. What's the function of the Black wires attached to the contact plates? Is it possible for the Pinbank Selector to work correctly, select, and cancel with 4 wires detached? Thanks guys.

Yes, the SA will work,tho unreliably, with those wires broken. They merely provide a positive ground to the contacts. Sometimes it is possible for the contacts to pick-up the ground through the posts, or springs it "rides" on. Ron Rich

Yep, figured as much, many thanks Ron for your wisdom