Input Speed Sensor and Output Speed Sensor (Hardwired)

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The input speed sensor provides information to the TCM on how fast the torque converter turbine is spinning. The sensor is located on the front side of the transaxle case, close to the bellhousing. The Input Speed Sensor is a two wire magnetic pickup sensing device. As the teeth of the input clutch hub pass by the sensor coil and magnet, an AC voltage proportional to shaft rotation is induced into the coil of the sensor. This AC signal is sent to the TCM. The TCM interprets this information as input shaft rpm. This information is also compared to the output shaft speed and the engine speed signal to determine the following:
- Planetary gears operating ratio
- Torque converter clutch slippage
- Torque converter element speed ratio
The output speed sensor is located on the same side of the transaxle case as the input speed sensor, but much closer to the end of the transaxle. The output speed sensor generates a signal from the rotation of the rear planetary carrier park pawl lugs passing by the sensor. When the output speed sensor signal is received by the TCM, the signal is compared to the input speed signal to determine gear ratio, detect clutch slippage, etc.