I know it's been a while since this thread. But for anyone that is researching start problems, here is what I found on my TC45D.
Intermittent start problems. Had to wiggle shifter past "N" several times to start. Sometimes start relay would click, sometimes not. Traced it to the "transmission range switch" on driver's side of transmission case. This switch is part of the safety interlock system for starting. I removed the switch. (unplug 2 bullet connections) use 3/4" open end, unscrew from transmission. I hooked meter on the leads, pushed the spring loaded button, and found sometimes it made contact, sometimes not. So, I chucked the little "nipple" or button in my cordless drill, and slowly turned it several times. Seems to have cleared some sort of debris or oxidation inside the switch body, as now it makes and breaks contact as it should. Replacement is about $46. Hope this works.