Abstract: Parking machines communicate automatically with service personnel located at a central station in response to the occurrence of a machine error. The service personnel are thus made aware promptly of this situation without having to travel to the site of each parking machine so that appropriate action can be timely taken. The parking machine stores an error signal, and the telephone number of the central station is then dialed. When a communication link is established telephonically, an audible message is generated by the parking machine and transmitted to the central station identifying the parking machine and a machine error. As long as the machine is not serviced, it will re-dial the central station to transmit the error message, and this is repeated at a time interval set according to whether the error has disabled the parking machine or not.