your going to laugh really hard
1st. does the od light blick or come on momentarily when you turn the key on while waiting for the glow plugs to go off?
2nd if it does as part of the start up sequence then its an intermittent problem.
if you look at the steering colum cover where the shifter stalk goes in to the rubber booty, gently slide the part of the booty that goes around the shifter back to expose the little bity wire that comes out of the side of the stalk and goes into the colum., more than likely its chaffed through from the hard plastic of the colum cover( it gets hit every time you tilt the wheel all the way down to drive, yeah its odd ) your ma y not be chaffed complety through or it is but still has some intermittent contact.
the repair is cake, remove the steering colum cover, pop out the shifter stalk pin, and replace the shifter. or do like a lot of folks, remove the stalk, and rewire it with the new wire on the outside of the stalk wrapped in heat shrink and eliminate the pinch point at the colum. its an issue that happens very often, but they refuse to do a recall or campaign to fix em.
good thing is if you have an 04 or higher with the tq shift the button is wired different
hope it helps