Abstract: The disclosure describes an improved apparatus for testing a wheeled vehicle utilizing wheel-supporting rollers. All the wheel-supporting rollers are constrained to rotate at the same peripheral speed. Means are provided for measuring the angular acceleration or deceleration of the rollers.

Abstract: In automatic diagnosis equipment for automobiles, it is essential for proper results that the datacarrier which carries the coded vehicle specifications corresponds with the vehicle to be tested. The present invention provides a system for checking correspondence between the datacarrier and the car to be tested which comprises a code-key in which the car characterizing code is recorded, said code corresponding with a code recorded on the datacarrier, and means for reading out the code on the code-key and the code on the datacarrier, for comparing them and for signaling and/or blocking the test program in the event of absence of agreement.