What is toyota vitz scp 10 p0500 fault - 2001 Toyota Yaris

"Vehicle Speed Sensor Malfunction". That may be either related to the speedometer or related to the ABS, if your Yaris is equipped with ABS. It indicates that the car THINKS that it should be able to sense how fast the wheels are turning when you're in motion, but it's getting a strange signal from the sensor.

Since this is a Yaris with front-wheel drive, your speed sensors will be somewhere between the transaxle and the front wheels, probably one on each side. Look for some sort of small device mounted next to the axle shafts or next to the brakes - that device should have wiring connected to it. Check the little electrical connector, make sure it's plugged together correctly. The sensor itself may have failed, though, so be prepared to replace one or the other. if replacing one doesn't solve the problem, put the original one back and use the new one to replace the sensor on the other side of the car.