Code 58, Transmission Temp. Sensor CKT (High Temp. Indicated): Notes

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The transmission temperature sensor is a thermistor which controls the signal voltage to the PCM/TCM. The PCM/TCM applies and monitors voltage on circuit No. 1227 to the sensor. When transmission is cold, sensor resistance is high; therefore, the PCM/TCM will see high signal voltage. As the transmission warms up, sensor resistance and voltage will drop. At normal transmission operating temperature of 212°F (100°C), voltage will be about 1.5-2.0 volts.

NOTE: Test numbers refer to test numbers on diagnostic chart.

Code 58 will set if signal voltage indicates a transmission temperature greater than 309°F (154°C) for one second.
This test determines if circuit No. 1227 is shorted to ground, which will result in conditions for Code 58.