Our bot from last year has 2 Vex 393 motors (using the Vex motor controllers) and one HiTechnic servo (from KOP).
Until today all 3 were working, but as of today only the servo is working correctly. We tried replacing the 393 motors, we also tried replacing motor controllers for the 393’s. We even tried swapping them to 2 unused PWM ports on our DSC. Nothing worked.
When we activate these motors the click and move very slowly until you give them a kick. Then they start working correctly.
Did you plug a 393 into the port that has the servo working? Have you looked at the voltage coming out of the vex speed controllers with a multimeter? Have you looked at the voltage coming out of the sidecar?
If needed you can run the 393 motors off of a Victor/Jaguar/Talon. We ran two off of a talon all year without problems. We did’t give them full power in programing; we ran them up to around 10v.