Sharp R-22AM Service Manual

15
R-22AM
R-23AM
R-23AT
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
1. CARRY OUT 3D CHECKS.
2. A continuity check across the temperature fuse terminals should indicate a closed circuit unless the
temperature of the temperature fuse reaches specfied temperature as shown below.
I TEMPERATURE FUSE TEST
3. CARRY OUT 4R CHECKS.
CAUTION: IF THE temperature fuse INDICATES AN OPEN CIRCUIT AT ROOM TEMPERATURE,
REPLACE temperature fuse.
Open Close Display or
temperature temperature Condition Check point
Magnetron tem-
perature fuse
TF1
Magnetron tem-
perature fuse
TF2
Blower motor tem-
perature fuse
TF3
Oven temperature
fuse
TF4
150˚C
120˚C
120˚C
Non resetable
type
Non resetable
type
Non resetable
type
EE1
EE3
EE2
Oven shut
off
Oven shut
off
Magnetron
MG1 Failure:
Test magnetron
MG1 and Blower fan motor.
Magnetron MG1, MG2 Failure: Test magnetron MG1,
MG2. Check blower fan motor and ventilation opening.
Magnetron MG2 Failure:
Test magnetron
MG2 and Blower fan motor.
Check blower fan motor and ventilation opening or
rocked rotating of blower fan motor.
Food has been burned in oven.
Temperature of oven inside is very high.
J MONITOR RESISTOR R1 TEST
CARRY OUT 3D CHECKS.
Disconnect the leads from the monitor resistor R1. Using an ohmmeter and set on a low range. Check
between the terminals of the monitor resistor R1.
The resistance of monitor resistor R1 should be read approx. 4.3Ω.
If incorrect readings are obtained, replace the monitor resistor R1.
CARRY OUT 4R CHECKS.
1. CARRY OUT 3D CHECKS.
2. Follow the procedures below for each thermistor.
2-1. MAGNETRON THERMISTOR TEST
Disconnect the connector of the magnetron thermistor from the switch harness. Measure the
resistance of the magnetron thermistor with an ohmmeter. Connect the ohmmeter leads to the leads
of the thermistor.
Room Temp. 59˚F (15˚C) 68˚F (20˚C) 77˚F (25˚C)
Resistance Approx. 373 kΩ Approx. 292 kΩ Approx. 231 kΩ
If the meter does not indicate above resistance, replace the thermistor.
2-2. OVEN THERMISTOR (1) TEST
Disconnect the connector of the oven thermistor (1) from the switch harness. Measure the resistance
of the oven thermistor (1) with an ohmmeter. Connect the ohmmeter leads to the leads of the thermistor.
Room Temp. 59˚F (15˚C) 68˚F (20˚C) 77˚F (25˚C)
Resistance Approx. 373 kΩ Approx. 292 kΩ Approx. 231 kΩ
If the meter does not indicate above resistance, replace the thermistor.
2-3. OVEN THERMISTOR (2) TEST
Disconnect the two connectors of the magnetron thermistor and oven thermistor (2) from the switch
harness. Measure the resistance of the oven thermistor (2) with an ohmmeter. Connect the ohmmeter
leads to the leads of the thermistor.
K THERMISTOR TEST

Sharp R-22AM Specifications

General

Brand	Sharp
Model	R-22AM
Category	Microwave Oven
Language	English