R-216 (serv.man2). Complete - Sharp Home Appliance Service Manual (repair manual). Page 11

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Disconnect the leads from the terminals of the thermal cut-out. Then using an ohmmeter, make a
continuity test across the two terminals as described in the below.

CARRY OUT 4R CHECKS.

Table: Thermal Cut-out Test

Temperature of "ON"

Temperature of "OFF"

Indication of ohmmeter (When room

Parts Name

condition (closed circuit).

condition (open circuit).  temperature is approx. 20˚C.)

Thermal cut-out 95˚C (MG.)

 Below 75˚C

Above 95˚C

Closed circuit.

Thermal cut-out 125˚C (OVEN)

This is not resetable type. Above 125˚C

Closed circuit

If incorrect readings are obtained, replace the thermal cut-out.

An open circuit thermal cut-out (MG) indicates that the magnetron has overheated, this may be due
to resistricted ventilation, cooling fan failure or a fault condition within the magnetron or HV circuit.

An open circuit thermal cut-out (OVEN) indicates that the food in the oven cavity may catch fire, this may
be due to overheating produced by improper setting of the cooking time or failure of the control panel.

CARRY OUT 3D CHECKS.

Disconnect the leads from the motor. Using an ohmmeter, check the resistance between the two
terminals as described in the table below.

Table: Resistance of Motor

Motors

Resistance

Fan motor

Approximately 400 

Ω

Turntable motor

Approximately 12 k

Ω

If incorrect readings are obtained, replace the motor.
CARRY OUT 4R CHECKS.

CARRY OUT 3D CHECKS.

If the fuse T6.3A is blown when the door is opened, check the monitored latch switch and monitor
switch.
If the fuse T6.3A is blown by incorrect door switching, replace the defective switch(s) and the fuse
T6.3A.
If the fuse T6.3A is blown, there is a shorts or grounds in electrical parts or wire harness.
Check them and replace the defective parts or repair the wire harness.
CARRY OUT 4R CHECKS.

CARRY OUT 3D CHECKS.

Disconnect the leads from the terminals of noise filter.
Using an ohmmeter, check between the terminals as described in
the following table.

Between N and L

Open circuit

Between terminal N and WHITE

Short circuit

Between terminal L and RED

Short circuit

If incorrect readings are obtained, replace the noise filter unit.

CARRY OUT 4R CHECKS.

FUSE
T6.3A

N

L

LINE CROSS CAPACITOR

0.068

µ/AC250V 

NOISE SUPPRESSION COIL 

LINE BYPASS
CAPACITOR
0.0022

µ/AC250V

LINE BYPASS
CAPACITOR
0.0022

µ/AC250V

NOISE FILTER

WHT

RED