LEMON Manuals: Even more car manuals for everyone
Home >> Hummer >> 2008 >> H2 4D Utility Wagon >> Repair and Diagnosis >> External Pages >> Different car >> Section 132 (Automatic Transmission - 4L60-E/4L65-E/4L70-E - Introduction (2 Of 2)) >> Description and Operation >> Electronic Component Description (TCM) >> Automatic Transmission Fluid Temperature Sensor

Automatic Transmission Fluid Temperature Sensor

WARNING: This page is about a different car, the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

The automatic transmission fluid temperature (TFT) sensor is part of the automatic transmission fluid pressure (TFP) manual valve position switch. The TFT sensor is a resistor, or thermistor, which changes value based on temperature. The sensor has a negative-temperature coefficient. This means that as the temperature increases, the resistance decreases and as the temperature decreases, the resistance increases.

The transmission control module (TCM) supplies a 5-volt reference signal to the TFT sensor and measures the voltage drop in the circuit. When the transmission fluid is cold, the sensor resistance is high and the TCM detects high signal voltage. As the fluid temperature warms to a normal operating temperature, the resistance becomes less and the signal voltage decreases. Refer to Transmission Fluid Temperature Sensor Specifications  for a complete comparison of sensor resistance, temperature and signal voltage.

The TCM uses the TFT sensor information to control shift quality and torque converter clutch (TCC) application.

scientia non olet · About LEMON Manuals