94 2500 240k 4x4 auto. Transmission temp light would intermittently come on and not allow the torque converter to lock up or shift into overdrive. Transmission is not hot when the light is on, fluid is usually cold or just warm on the dipstick. Transmission temp light is on all the time now, and it only shifts into 1,2, and 3. I tried unplugging the sensor, also put a jumper wire in the plug, neither made any difference. Just curious if any of you have any ideas of where to start to look for the wiring problem. Thanks

 

After you unplug the sensor jump across the two wires going towards the computer with a 1000 ohm resistor, 25¢ Radio Shack.
Don't plug the sensor back in.
This tricks the computer into thinking the fluid is at operating temp.
Good time to install an aftermarket tranny temp gauge, leave the resistor in place.

 

i can attest to this advice from bill it works great i put the resistor in and havent looked back no problems whatsoever

 

Thanks for the advice, fixed the problem. Anybody know what kind of threads on are on the factory temp sensor? Could I just screw in an aftermarket gauge sensor into this hole? I tapped a hole in the trans pan on my other truck, if I could avoid that it would be great.

Thanks

Matt

 

The stock port is female 3/8" pipe thread.
Most aftermarket probes are 1/4" pipe thread so all you need is a reducer bushing from the hardware store.
Some gauge kits include a bushing.

 

Thank you very much for the info and the help, I greatly appreciate it.

Matt

 

im converting my hard lines to rubber lines so ill be making a sensor block to put inline that will hold my sensor