For lack of a better way of explaining it, the controller on your golf cart acts as the brain of the whole operation. Everything that has a wire or a cable running to it communicates signal back to the controller at some point or another. Even the motor, which you would think would be the final step in the process, has its share of info to report back. The controller needs to know the RPM of the motor to be able to determine how much power to send it. If this information is not received, the brain of your coach will lock you into a low-speed safety mode. If this sounds like it is happening to you, you may need to replace the E-Z-GO PDS Speed Sensor Magnet.The golf cart magnet is attached to the armature of the motor. A speed sensor sits on top of it and communicates the revolutions back to the E-Z-GO controller. We recommend that you get both of these parts as either can cause the same issue. Call Buggies Unlimited today and get set up with everything you need.