My guess is that you will need electronic cruise contol/ pto feature to make this work. It is going to come down to whether your ECM calibration supports pto or not. You probably cannot put the newer calibrations in the older ECMs'.
If you have a newer truck and it is not working then the pto rpm may be set the same as your idle rpm, at that point a simple change of parameters is all that is needed, not a complete reflash.
The DRB tool probably is not reading it because the calibration does not support it.
A Johnson
If you have a newer truck and it is not working then the pto rpm may be set the same as your idle rpm, at that point a simple change of parameters is all that is needed, not a complete reflash.
The DRB tool probably is not reading it because the calibration does not support it.
A Johnson