R-8580
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER COMPONENT TEST
CHECKING CONTROL UNIT
(1) Disconnect oven from power supply and remove outer case.
(2) Discharge the high voltage capacitor.
(3) Disconnect the wire leads from the cook relay.
(4) Disconnect the sensor connector that is mounted to lower position of control panel.
(5) Then connect the dummy resistor circuit (see fig.) to the sensor connector of control panel.
(6) Reconnect the oven to the power supply and check the sensor cook operation proceed as
follows:
6-1. Touch SENSOR COOK pad and number 0 pad.
6-2. The control panel is in the sensor cooking operation.
6-3. After approximately 20 seconds, push plunger of select switch.
This condition is same as judgement by AH sensor.
6-4. After approximately 3 seconds, cooking operation turns off, an audible signal will
sound, and the display will then revert to the time of day.
If the above is not the case, the control unit is probably defective.
If the above is proper, the AH sensor is probably defective.
Plunger
0-J
To Connector (F)
on Control Untt
CONNECTOR
NC
NO
Rl, R2 : loon t 1% 1/2w
R3 : 10kR ? 5% 1/4W
R4 : 12kR * 5% 1/4W
F-l -
F-2..--
F-3 rc-
I Switch
R2
R4
iNO.
-2
Sensor Dummy Resistor Circuit
R PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING
BOARD(PWB) IS OPEN.
To protect the electronic circuits, this model is provided with a fine foil pattern added to the
primary on the PWB, and this fine pattern service as a substitute coil. If the foil pattern is open,
follow the troubleshooting guide given below for repair.
_ .--
Problem: POWER C
JN, indicator does not light up.
STEPS
OCCURANCE
CAUSE OR CORRECTION
1 The rated voltage is not applied to POWER terminal Check supply voltage and oven main unit.
of CPU connector (CN-A)
2 The rated voltage is applied to primarv side of Dower Power
transformer or secondarv circuit defective.
NOTE:* At the time of these repairs, make visual in-
spection of the varistor for burning damage
and examine the transformer with tester for the
presence of layer short-circuit (check primary
coil resistance).
If any abnormal condition is detected, replace
the defective parts.
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