Component Test Procedure - GE JES2251SJ Technical Service Manual

8 COMPONENT TEST PROCEDURE

CAUTIONS NEW. H.V.
1.High voltage is present at the high voltage
terminal of the High Voltage Inverter (U)
including aluminum heat sink during any cook
cycle.
2.It is neither necessary nor advisable to attempt
measurement of the high voltage.
3.Before touching any oven components, or
wiring, always unplug the oven from its power
source and discharge the high voltage
capacitors.
8.1. Primary latch switch (door switch
and power relay B) interlocks.
1. Unplug lead connectors to Power Relay B and
verify open circuit of the power relay B 1-2
terminals.
2. Unplug lead connectors to Primary Latch Switch
and Door Switch.
3. Test the continuity of switches at door opened and
closed positions with ohm meter (low scale).
Normal continuity readings should be as follows.
Primary Latch switch
Door Switch
Power Relay B
8.2. Short switch & monitor
1. Unplug lead wires from Inverter Power Supply (U)
primary terminals.
2. Connect test probes of ohm meter to the
disconnected leads which were connected to
Inverter Power Supply (U).
3. Test the continuity of short switch with door opened
and closed positions using lowest scale of the ohm
meter.
Normal continuity readings should be as follows.
Door Opened
0
Door Closed Door Opened
0 (Close) (Open)
0 (Close) (Open)
(Open) (Open)
Door Closed
8.3. Magnetron
Continuity checks can only indicate an open filament
or a shorted magnetron. To diagnose for an open
filament or shorted magnetron.
1. Isolate magnetron from the circuit by disconnecting
the leads.
2. A continuity check across magnetron filament
terminals should indicate one ohm or less.
3. A continuity check between each filament terminal
and magnetron case should read open.
8.4. Membrane key board (Membrane
switch assembly)
Check continuity between switch terminals, by
tapping an appropriate pad on the key board. The
contacts assignment of the respective pads on the
key board is as shown in digital programmer circuit.
(Refer to Mini Manual)
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