TROUBLE DETECTOR FOR FRONT-REAR WHEEL STEERING VEHICLE

PURPOSE:To perform the detection of trouble accurately as well as to improve driving safety, by installing a detecting device of trouble in a setting steering angle ratio and another detecting device of setting trouble in a rear-wheel steering angle, in the case of such one that connects front-rear wheel steering transitions with a mechanical connecting mechanism. CONSTITUTION:In case of a front-rear-wheel steering vehicle which connects a front- wheel steering mechanism 1b to a rear-wheel steering mechanism 3b via a mechanical connecting mechanism 2, a steering angle ratio to be set by the steering angle ratio setting mechanism 4 installed in a part of the mechanical connecting mechanism 2 is altered and controlled by an alteration controlling device 5. In this case, there are provided with a steering angle ratio sensor 6a detecting the set steering angle, and a first trouble detecting device 6b detecting the setting trouble of a steering angle ratio by the steering angle ratio setting mechanism 4 on the basis of the detected steering angle ratio. And, also there is provided with a second trouble detecting device 7b which detects the setting trouble of a rear-wheel steering angle ratio by a rear-wheel steering angle sensor 7a detecting each steering angle of rear wheels 3a. And trouble in a front-rear wheel steering vehicle is detected by each output of these trouble detecting devices 6b and 7b.