Code 59, Transmission Fluid Temperature Low - All Models: Notes

1996 Chevrolet Sportvan Van Passenger Extended, 6.5 YSECTION Notes
WARNING: This page does not describe the selected car, but rather 19 other vehicles, including the 1996 Chevrolet Chevy Van, 1995 GMC Vandura Special, 1995 GMC Vandura, 1995 GMC Sonoma, and 1995 GMC Safari. However, it is still accessible from the selected car via links, so may be relevant.

Transmission fluid temperature sensor is a thermistor which controls signal voltage to control module. Control module applies and monitors 5 volts to sensor. When transmission fluid is cold, sensor resistance is high; therefore, control module will see high signal voltage. As transmission fluid temperature warms, sensor resistance and voltage 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 numbers on diagnostic chart.
  1. Code 59 will set if signal voltage indicates a transmission fluid temperature less than -34°F (-37°C) for one second.
  2. This test simulates Code 58. If control module recognizes low signal voltage (high temperature) and scan tester reads 305°F (151°C) or greater, control module and wiring are okay.
  3. This test determines if signal circuit is open. There should be 5 volts present at sensor connector if measuring with a DVOM.
RENDER: 1.0x

NO RELATED

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