R-64ST - 19
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
If the display fails to clear when the STOP
key is depressed, first verify the lead wire
harness is making good contact, verify
that the stop switch operates properly; that
is the contacts are closed when the door is
closed and open when the door is open. If
the stop switch is good, disconnect the
lead wire harness that connects the switch
unit to the main board and make sure the
stop switch is closed (either close the door
or short the stop switch connector). Use
the Switch unit matrix indicated on the
switch unit circuit and place a jumper wire
between the pins that correspond to the
STOP key making momentary contact. If
the assembly responds by clearing with a
beep the switch unit is faulty and must be
replaced. If the assembly does not
respond, the main board is faulty and must
be replaced. If a specific key does not
respond, the above method may be used
(after clearing the display) to determine if
the display unit or main board is at fault.
M
SWITCH UNIT TEST
1
2
3
4
SW2
5
6
SW3
SW4
SW5
SW6
SW7
CN-G
SW1
Remove the outer case and check voltage between Pin No. 1 and Pin No. 3 of the 3 pin connector
(A) on the control unit with an A.C. voltmeter.
The meter should indicate rated voltage, if not check oven circuit.
RY1, RY2 and RY3 Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation, dual
grill cooking operation, or grill cooking operation.
DC. voltage indicated .......... Defective relay.
DC. voltage not indicated .... Check diode which is connected to the relay coil. If diode is good,
control unit is defective.
RELAY SYMBOL
OPERATIONAL VOLTAGE
CONNECTED COMPONENTS
RY1
Approx. 24.0V D.C.
Oven lamp / Turntable motor / Cooling fan motor
RY2
Approx. 18.0V D.C.
Heating element
RY3
Approx. 18.0V D.C.
High voltage transformer
N
RELAY TEST
R64ST_S.MANUAL
12/8/01, 11:01 am
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