The L series is a line of vehicles designed by General Motors and sold under the Saturn name brand. The L Series are mid-sized sedans and station wagons. The Saturn L Series were equipped with a specialized speed sensor installed on the transmission. The speed sensor is responsible for monitoring the speed of the vehicle at any given time. The sensor relays the speed information to the vehicle computer, which then controls the speedometer. When you notice your speedometer not working properly, it's important to replace the speed sensor immediately.
Park the Saturn L vehicle on a level surface and turn the engine off. Allow the vehicle to cool down for about 45 minutes. The transmission becomes extremely hot while driving, so this will prevent potential burns.
Jack the front of the vehicle up. Give yourself enough room to slide under the Saturn. Slide under the vehicle and locate the speed sensor installed on the transmission. The speed sensor is found on the right side of the transmission, which is the passenger side. The sensor is a plug-type component with an electrical connector sticking out from it.
Unplug the electrical connector from the sensor. Squeeze the sides of the connector and pull straight off. You can now remove the sensor from the transmission.
Twist the sensor counterclockwise using a wrench. This will loosen and remove the sensor. Once the sensor is loose enough; pull the sensor from the transmission. Discard the faulty sensor.
Place the new sensor into the appropriate mount on the transmission. Secure the sensor; turn the sensor using the wrench clockwise until the sensor is tight. Plug the electrical connector into the new sensor. You will hear the connector click into place. The sensor is now replaced. Slide out of from under the vehicle and lower the jacks.
