Ah, the world of computer communications a la 1960's and 70's. I remember it well.

You might have two problems.

1. Despite the sockets having 9 pins (DB9 I will presume), they might not all be connected. It depends how good the switch is. Basic serial comms only required three lines (Gnd, Rx and Tx) and some switches switched only these.

2. You might have trouble with the current rating. From your description I presume you are talking about the wiring between the drivers and the motors. In which case you are talking about a couple or more amps at tens of volts. Serial comms deals with currents of milliamps. Your switch might simply not be able to take the load. Without either looking inside to see how it is constructed or taking the risk of meltdown it is difficult to tell.

If, however, your switch is a good old mechanical one, similar to this http://uk.rs-online.com/web/search/s...duct&R=3901697 which has DB25 connectors, then you might just get away with it. I would open the lid and take a look inside.