Transmission Temperature Sensor

The transmission temperature sensor is a thermistor, or variable resistor, that varies in resistance based on temperature. The sensor is a "two-wire" sensor with a reference ground on Pin B (CKT 476). As temperature sensor increases, sensor resistance decreases. As resistance decreases, signal voltage from ECM decreases due to less voltage drop across transmission temperature sensor. High temperature will result in low signal voltage on CKT 520 and low temperature will result in high signal voltage on CKT 520.