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Input Speed Sensor

DESCRIPTION

Fig. 19:




Fig. 20:





The Input Speed Sensor is a two-wire magnetic pickup device that generates AC signals as rotation occurs. It is threaded into the transaxle case (Fig. 19), sealed with an O-ring (Fig. 20), and is considered a primary input to the Transmission Control Module (TCM).

OPERATION

Fig. 21:





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 (Fig. 21), an AC voltage is generated and sent to the TCM. The TCM interprets this information as input shaft rpm.

The TCM compares the input speed signal with output speed signal to determine the following:
- Transmission gear ratio
- Speed ratio error detection
- CVI calculation

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