Commander 4WD V8-4.7L VIN N (2006)
Transmission Speed Sensor: Description and Operation
The Input and Output Speed Sensors are two-wire magnetic pickup devices that generate AC signals as rotation occurs. They are mounted in the left
side of the transmission case and are considered primary inputs to the Transmission Control Module (TCM).
The Input Speed Sensor provides information on how fast the input shaft is rotating. As the teeth of the input clutch hub pass by the sensor coil, an AC
voltage is generated and sent to the TCM. The TCM interprets this information as input shaft rpm.
The Output Speed Sensor generates an AC signal in a similar fashion, though its coil is excited by rotation of the rear planetary carrier lugs. The TCM
interprets this information as output shaft rpm.
The TCM compares the input and output speed signals to determine the following:
Transmission gear ratio
Speed ratio error detection
The TCM also compares the input speed signal and the engine speed signal to determine the following:
Torque converter clutch slippage
Torque converter element speed ratio