Main electronic circuit board failed: has clock, push panels/buttons for oven, oven cleaning LOCK, clock display and oven temp more-less" controls in 3x8x1" unit with clock. "LOCK:" self cleaning light on when oven is UNlocked. So oven won't heat. Cost=rediculous--2/3 of price of stove in 2002 used only 3 mo./year unit clean, no visible damage. No dust, grease, water or dirt. HOW FIX or get used or cheap replacement??