When you say XR25, is it a genuine ex dealer item or the lap top based version that has been available to download?
And as Dave asked which car?
I can tell the basic method for the dealer XR25 and is common on vehicles with true TPS.
With just the ignition on (so no engine running) Once the equipment has initialised type D03 or D13 depending on vehicle & system
Look at bar graph labelled "throttle position" ( normally line 10 or 11) which should indicate the current status of the throttle with black bar/dot.
LH side is no load & RH is full load
Type #17 & this will give you a reading between 0 -255
With the throttle fully closed & the throttle cable and butterfly stop correctly adjusted (technically the stop is not adjustable) loosen slightly the two screws that clamp the throttle pot to the body and gently move the pot until #17 displays around 3-5.
It is at this point we need to know what vehicle it is as the base number will vary between vehicles.
If we take a R21t as an example the base figure is around 4 with no load.
Tighten the two screws gently and apply full throttle a couple of times using the pedal first & then directly on the body and make note of the reading on the #17 display, this should be between 235 & 255 but again it will vary slightly between models & systems.
That is the basic version but we need to known what XR25 version you have & vehicle once we got that there are other codes which will help identify the injection system id and the set up numbers for that system.