Case DX-35 PTO speed not illuminating.

[Jeepnford]

I have a 2003 DX-35. When the PTO is engaged the speed indicator on the dash will not illuminate when I speed up the PTO. The bulb is good since it lights up when you start the tractor. I thought maybe it had a hall effect sensor somewhere, but I am unable to find out any info. Anyone have any ideas?