Easy to fix.  Buy a new switch from the dealer and replace it.  If you
let the heater fan run on high for a long time the switch can overheat
and melt.  This happened to me when I was trying to thaw out the van
once after a snow storm, and I left it running on high for about 30
minutes while I went in for a cup of coffee.
--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

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