Hi I fix these for a living. This failure must be the most common 4250 one.
the temp sensr board has failed, it sits under the bottom heat roller. GBC charges near 200 bucks for the board:( but all thats wrong with it is a failed transistor. LM135 available from digi key for 13 bucks.
if you want directions on replacement thats fine. or you can call me.hone help is FREE
bob haller service and sales pittsburgh pa 412 366 4906, April 2012
