4L80e, do I need the temp sensor?

[Pettersson]

Hi all.
Do I need a working temp sensor inside my 4L80e?
Funny thing is that I have the sensor, but no connector, no wire and no traces of any cut wire.
Like GM decided that no sensor was needed, but they were out of plugs so they used a sensor as a plug.
Thanks.
/Peter

[Bernard Fife]

Peter,

I thought the 4L80E temperature sensor was in the the main plug (on pins L and M), not a separate unit.

In any case, the controller doesn't need the temperature sensor. It is used mostly for locking the TCC if the temperature gets too hot (and keeping it unlocked if the trans is too cold), so those functions won't be available to you. There is also a temperature related pressure control PWM adjustment factor which you won't be able to use. Of course you won't be able to monitor the trans temperature as you tune, etc. either.

If you are comfortable with those limitations, you don't need a temperature sensor for MShift's sake. Just leave the GPIO's temp wire (Amp pin 30) unconnected (snip it off and tape it up), and the code should think the trans is 180 degrees F all the time.

Lance.

[gui67]

The sensor is in the wire loom inside the pan. it is directly connected to the main connector as Lance said.

[Pettersson]

Thanks for quick replys!
Inside the loom, OK I'll check that when I'm home again.
I'd like those features, so I sure don't want to be without one.

But what is then the sensor I thought was the temperature sensor?
It's the thing to the very left:

[Pettersson]

Anyway, I checked the wiring today and the temp sensor is in the loom, just like you said.
Thanks guys!

[gui67]

Hello Peter, I don't know what this sensor is. I don't remember if I have it on mine.
What year is your transmission? Mine is an early one. (it had the first version of connector)

[Pettersson]

Sorry I don't know anything about this transmission.
The only readable lable says "Remanufactured for general motors"

[rxl158]

Thanks for quick replys!
Inside the loom, OK I'll check that when I'm home again.
I'd like those features, so I sure don't want to be without one.

But what is then the sensor I thought was the temperature sensor?
It's the thing to the very left:

Petersson, the round unit in the upper left on your valve body in the pic is the Force Motor.
It controls or influences line pressure by a PWM signal from the GPIO.