Transmission temp light on

[DonFitzwater]

I'm getting a transmission temp light occassionally. It comes on at odd times. Cold start up, sitting idling when warm, driving accross parking lots. There is no ryhm or reason with it. My trans temp never gets over 140 (summer) and rarely gets above 100 (winter). My temp sender for gauge is in the pan. I pulled it out of a warm garage yesterday and left it outside at high idle and trans in neutral and in about 10 minutes the temp light was on with no temp registering on the gauge. I even got under the truck and shot the transmission pan and cooling lines with a temp gun and they were cold 50-70 degrees. Any ideas? My dealer here is pretty much worthless with troublshooting unless the part falls off while in for diagnosis so I think they are out of the question.



P. S. No DTC stored. Light comes on and bell sounds but light will go off and no code is stored (at least that I can retrieve with the key on off trick. )

 

[rbattelle]

Sounds to me like a short in the transmission temperature sensor. Check resistance across the sensor - should be ~2000 ohm at room temperature.

The sensor is part of the governor pressure sensor assembly, so you have to remove the pan to access it.

Ryan

 

[ACamilli]

Yes, that happened to me on my 2006 drw a few weeks ago first thing in the very cold morning, at start-up! Went off after a few minutes