2005 5R55S Transmission Fluid Temperature Sensor TFT

[chezzrob]

Greetings, seeking info on how to test the Transmission Fluid Sensor to see if it is recording a proper temperature reading. The schematic shows that it it is in the transmission.

Is the TFT sensor accessible or transmission has to be stripped?
How would you test it, assuming it is a few degrees out of wack.

There are no codes recorded that TFT is a problem, but I need this info in fault finding another problem with the TCC solenoid. Apparently the TFT is an input to the PCM that needs to be satisfied before the TCC solenoid is powered. What would the oil temp be required> Hot or Cold.

The problem seems to occur when the oil is hot so if the sensor is inaccurate by say 50F it may be saying that the oil is hotter than it ireally is.
Anyone know if it is hot oil that prevents the TCC solenoid from operating or if the oil is to cold?

 

[imp]

Greetings, seeking info on how to test the Transmission Fluid Sensor to see if it is recording a proper temperature reading. The schematic shows that it it is in the transmission.

Is the TFT sensor accessible or transmission has to be stripped?
How would you test it, assuming it is a few degrees out of wack.

There are no codes recorded that TFT is a problem, but I need this info in fault finding another problem with the TCC solenoid. Apparently the TFT is an input to the PCM that needs to be satisfied before the TCC solenoid is powered. What would the oil temp be required> Hot or Cold.

The problem seems to occur when the oil is hot so if the sensor is inaccurate by say 50F it may be saying that the oil is hotter than it ireally is.
Anyone know if it is hot oil that prevents the TCC solenoid from operating or if the oil is to cold?

The TFT does indeed "enable" all three speed sensors as pointed out earlier today in thread entitled "2005 V-6 Explorer Burnt Out Torque Converter Clutch", Post #6 , where I posted the complete wiring diagram for the 5R55S. Look that over, your answers may be there. You need to be aware that if the TFT malfunctions, PCM is capable of giving codes for that. If you do not have TFT codes generated, you may be going in the wrong direction.

To answer one of your questions, the TFT is contained within the solenoid module, and is not directly accessible (for replacement purposes); however, it's output voltage may be checked OUTSIDE of the transmission at the electrical connector there. If you feel you still need TFT related info, let us know, and I'll gather it together for you. imp

 

[Rstaurowsky]

Is there a way to determine if the torque converter is causing the transmission to overheat and burn the fluid?