Transmission Fluid Temperature Sensor
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Located in the transmission oil sump, the NTC oil temperature sensor's ohmic value decreases as the temperature increases. The GS 20 monitors the fluid temperature by sensing the voltage drop across the sensor causing a standing monitor voltage to "bleed" to ground. Rise and fall of the standing voltage value is a direct correlation of the fluid temperature. Detection of high fluid temperature modifies the torque converter regulation control and modifies the shift program to aid in reducing transmission fluid temperature. If the signal becomes impaired, the GS 20 applies a substitute temperature value based on engine temperature via CAN and stores a specific fault code.