Wired remote for Aquabot Turbo

I have an older Aquabot Turbo with a wired remote control unit that allows the user to steer the bot to the left or right. The remote plugs into the power supply box via a connector similar to that of a telephone cord but smaller in size. I am getting a red light on the remote when one of the direction buttons are pressed but no response at the plungers on the side of the robot that extend to perform the requested turn. Any ideas as to why the plungers are not extending? A schematic diagram would be helpful as to determine the source of power for the plungers to operate.