Location of the Speed Sensor in the Scion XBby Marion Cobretti
The speed sensor (or, as Scion refers to it, "transmission revolution sensor") monitors your XB’s transmission to determine how fast you’re traveling. This information is sent to your car’s computer and it relays it to your speedometer. A defective speed sensor will affect many vehicle functions. Problems with the cruise control feature is one of the first signs of a problem. The sensor may also send false speed readings to the computer that are as much as 10 to 15 miles per hour lower or higher than your actual speed. You can locate the speed sensor on your Scion XB in a few minutes. Replacing the transmission revolution sensor will take around 25 minutes.
Raise the hood on your XB and locate the engine’s air cleaner assembly. The assembly houses your air filter and is mounted on the right side of your engine compartment. It has a large black rectangular cover and a big black tube coming out of the left side of it.
Locate the air cleaner assembly’s mounting bracket. The bracket sits under the lower portion of the assembly. Four inches to the left--horizontal--of the bracket, you will see a small wiring harness plug connected to the transmission by one bolt. The harness plug attaches to your transmission revolution sensor.
Unplug the wiring harness connected to the transmission revolution sensor by hand. Do not use any tools because you might damage the harness plug.
- You will most likely have to remove the air cleaner assembly for full access to the sensor. Take the lid off the air cleaner assembly and remove the filter. At the bottom of the lower half of the assembly, you will see three bolts. Remove the bolts with a socket wrench and lift the assembly out of your XB’s engine compartment. Remove the sensor from the transmission with your socket wrench as well. Install a new rubber O-ring around the base of the new sensor. The new sensor won’t come with a new O-ring but you can find them at any auto parts store.
Things You'll Need
- Socket wrench set
Marion Cobretti began working as a freelance writer in 2006. His work appears on Newsvine and other websites. Cobretti completed a three-year course in automotive technology and is currently seeking an Associate of Applied Science at Macomb Community College.