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Transmission Temperature Sensor

NOTE: The transmission temperature sensor is used on models equipped with an automatic transmission and a factory installed transmission cooler.

DESCRIPTION
The transmission temperature sensor is a variable, thermistor type. It reacts to temperature changes. At cold transmission oil temperatures, its resistance is high. As temperatures increase, its resistance will decrease.

PURPOSE
Its purpose is to help control transmission fluid overheating.

Transmission Temperature Warning Lamp:





OPERATION
If transmission overheating has been determined by this sensor (temp. above approximately 280 degrees F), an input is sent to the Powertrain Control Module (PCM). The PCM will then force a 4-3 down-shift. Once transmission temperature has cooled below specifications, a 3-4 upshift will be allowed. An instrument panel mounted transmission temperature warning lamp is also used.