Code 58, Transmission Fluid Temperature High: Notes

The transmission fluid temperature sensor is a thermistor which controls the signal voltage to the PCM/TCM. The PCM/TCM applies and monitors voltage to the sensor. When transmission fluid is cold, sensor resistance is high; therefore, the PCM/TCM will see high signal voltage. As the transmission fluid 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.

1. Code 58 will set if signal voltage indicates a transmission fluid temperature greater than 305°F (151°C) for one second.
2. This test determines if circuit is shorted to ground, which will result in conditions for Code 58.