Circuit/System Description

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The automatic transmission (AT) input and output speed sensor (ISS and OSS) assembly each are part of a single harness. The ISS is a hall-effect type sensor. The sensors mount to the control valve upper body assembly. The assembly connects to the control solenoid (w/body and TCM) valve assembly through a 3-wire harness and connector. The sensor end faces the 1-2-3-4 and 3-5-R clutch housing machined teeth surface. The sensor receives 8.3-9.3 volts on the input/output speed sensor (ISS/OSS) Supply Voltage circuit from the transmission control module (TCM). As the 1-2-3-4 and 3-5-R clutch housing rotates, the sensor produces a signal frequency based on the machined surface of the clutch housing. This signal is transmitted through the ISS signal circuit to the control solenoid (w/body and TCM) valve assembly. The control solenoid (w/body and TCM) valve assembly uses the ISS signal to determine line pressure, transmission shift patterns, torque converter clutch (TCC) slip speed and gear ratio.