14
R-15AT
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
2-3 Other possible troubles caused by defective control unit.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable
is marking good contact, verify that the primary interlock relay control switch operates properly; that
is the contacts are closed when the door is closed and open when the door is open. If the primary
interlock relay control switch is good, disconnect the flat ribbon cable that connects the key unit to the
control unit and make sure the primary interlock relay control switch is closed (either close the door
or short the primary interlock relay control switch connecter). Use the Key unit matrix indicated on the
control panel schematic and place a jumper wire between the pins that correspond to the STOP/
CLEAR pad marking momentary contact. If the control unit responds by clearing with a beep the key
unit is faulty and must be replaced. If the control unit does not respond, it is a faulty and must be
replaced. If a specific pad does not respond, the above method may be used (after clearing the control
unit) to determine if the control unit or key pad is at fault.
L
KEY UNIT TEST
CARRY OUT 4R CHECKS.
M
RELAY TEST
5
6
3
4
1
11
13
15
19
12
14
16
20
17
18
2
7
8
9
0
G12
G11
G10
G 9
G 1
G 2
G 3
G 4
G 5
G 6
G 7
G 8
DOUBLE
QUANTITY
EXPRESS
DEFROST
SELECT
POWER
START
SET
CHECK
SIGNAL
STOP/
CLEAR
X
2
SELECT
TIME
CARRY OUT 3D CHECKS.
Remove the outer case and check voltage between Pin Nos. 3 and 7 of the 3 pin connector (A) on the
control unit with an A.C. voltmeter.
The meter should indicate 230 volts, if not check oven circuit.
Relay Test
Check voltage at the relay coil with a D.C. voltmeter during the microwave 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
RY2
Approx. 18.0V D.C.
High voltage transformer
RY3
Approx. 18.0V D.C.
Oven lamp / Antenna motor / Fan motor
CARRY OUT 4R CHECKS.
