Primary Speed Sensor (VSS)
*Located on the transmission housing
* Monitors vehicle speed using a rotating sensor that reads signals from the transmission output shaft
Turbine Input Shaft Speed Sensor (TIS)
*Located inside the transmission housing
* Monitors torque converter turbine input shaft rotation speed
*Used for precise gear shifting
Output Shaft Speed Sensor (OSS)
*Located on the transmission output shaft
* Monitors transmission output shaft rotation speed
*Used for precise gear shifting and cruise control
Reverse speed sensor
*Located on the transmission housing
* Monitors engagement of reverse gear
* Controls reverse gear lock and signals when reverse gear is engaged
Speed sensor errors
A faulty speed sensor can lead to the following problems:
* Incorrect speed or mileage indication
*Hard gear shifting
* Gear slippage
* Enabling “limp home” mode
*Reduced fuel efficiency