Just a few things that come to mind . Did you check to see if the pedal function is registering on the drum module as a seperate hit when pressing the pedal on the hi-hat stand ? Also don't take for granted that the module has the sound sample allready assigned for the pedal function , check to make sure that it has a seperate sound selected for it . I have a few times on my DTX 2.0 module had an open hats sound for both the foot pedal and a cymbal hit itself set for both functions so there wasn't a noticable difference . Also I know in Yamaha modules especially there's the ability to turn off specific trigger inputs ( this is more for midi and sampling purposes ) but you may want make sure that all of the hihat features are on and have the respective sounds assigned to them .
I do know that people have mentioned that you should have the Yamaha logo on the hihat facing toward you too , so I'm not sure if this sets an alignment for the hi hat pedal functions feature or not , but it might be worth checking out .
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