Hanssc

Hi! My XT125 from 2007 has a defect speedometer. It is a electronic display that shows different informations. It is showing the speed as 0 km/t and not counting the distance, but it is able to show the rpm. It has a sensorcable that ends with a sensor close to the break disk. Nothing is mounted on the disk, so I assume that it some kind of sensor that can see whether it is close to metal or not and is used for counting the holes in the breakdisk. Is that correct? I assume that the failure could have something to do with the sensor and want to check it. Do you know what kind of semsor it is (reedswitch, inductive or ??) and how to check it? There are three wires in the connector to the sensor. Has any of you had the same failure and what was the problem? Thank you in advance! Hans