The ambient air temp gauge
appears to use mode 1 pid 46
if your vehicle reports it.

Correct. But it seems I don´t get any feedback on this PID from my ECU.

Thats why I´m asking how Torque gets the ambient temperature.

I want to know too how torque gets this warning. I have no ambient temperature values, but also have icy warning. I think, that torque reads "intake temp" value. Anyone know this?

I figured it uses the vehicles ambient temp gauge. My F-150 has an outside temp readout and will display "ICE" when below 32F/0C; Torque follows suit and says "Warning, ICE" aswell.

Maybe, even if your car doesnt have one, the vehicle supports one via an optional package, thus has the external sensor

I believe that the Torque App predefined PIDs are programmed to pick which sensor or device it gets the value from to display. I can’t find the post but I remember a question asked about the where the Barometer readings come from. To make sure it was from my ECM to make a custom PID. To make a custom Boost PID equation I had to use Baro [33} that comes from Torque predefined till I learn how to put a custom PID in a formula.

I know my F350 has a separate external temperature sensor and the custom PID I’m using must be getting its value from there because it matches the display when the sun heats it up. I haven’t added the IAT yet so I can’t confirm.