There is a 5 volt regulator on the lower printed wiring board within the control assy. This regulator probably supplies the 5 volts for all the digital logic ICs in the control assy. A 33 uF capacitor on the output side of the regulator had gone bad (capacitance much too small) due to age, temperature extremes, etc. The regulator needs a minimum of 22 uF to work properly, per the manufacturer's data sheet for the regulator. I replaced the capacitor and another one just like it that was found on the upper printed wiring board...they both had the same bad appearance on visual inspection. My control assy part number is 124 830 18 85. Assy works fine after repair.