GE ZEK957 Series, Technical Service Manual

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Microwave Key Panel Test
The control panel circuits from the keys to the
PCB can be verified by a continuity test.
Refer to the chart in the mini-manual located
behind the control panel.
Microwave High-Voltage Capacitor
WARNING: Always be certain the capacitor is
discharged before servicing. Mechanically dis-
charge by placing an insulated handle screwdriver
between the diode connection of the capacitor and
the oven chassis ground.
Note: The high-voltage capacitor has an internal
shunt resistor that automatically discharges the
capacitor when the oven turns off. Under normal
operation, the capacitor should fully discharge
within 30 seconds.
The microwave must be removed from the oven
to service the high-voltage capacitor.
The high-voltage capacitor is mounted to the base
plate at the rear of the component compartment.
If the capacitor is open, no high voltage will be
available to the magnetron.
High-Voltage Capacitor Test
1. Disconnect the leads and check for short or
open between the terminals using an ohmme-
ter set on high ohm scale. If the capacitor is
normal, the meter will indicate continuity for a
short period and should indicate an open
circuit once the capacitor is charged.
2. If the above is not the case, check for a short
between either terminal and the case. If
shorted, replace the capacitor.
High-Voltage Capacitor
Diode