Are you still using the same switch as in this post?
Leo's switch

After 15 years, I wouldn't be surprised if it died. First thing to do is check that there is power to the switch.

If the switch is no longer working, ISTR that there was a thread on how to disassemble the switch and clean up the contacts. Maybe someone can find it?

Gord 🇨🇦
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1954 1/2 ton 235 4 speed