AX-1100(R)M, AX-1100(SL)M (serv.man8). Test Procedures - Sharp Home Appliance Service Manual (repair manual). Page 3

AX1100(R)M

9 – 3

CARRY OUT 3D CHECKS.

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.

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

An open circuit thermal cut-out (MG) TC1 indicates that the magnetron has overheated, this may be due to resistricted ventilation, cooling fan failure.

An open circuit thermal cut-out (OVEN) TC2 indicates that the oven cavity has overheated, this may be due to no load operation or fire in the oven
cavity.

An open circuit thermal cut-out (Engine) TC3 indicates that the engine unit has overheated, this may be due to empty water tank or pump motor fail-
ure.

CARRY OUT 4R CHECKS.

CARRY OUT 3D CHECKS.

If the fuse F1 20A 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.

CAUTION: Only replace fuse with the correct value replacement.

CARRY OUT 3D CHECKS.

1. If the fuse F2 F8A is blown when the door is opened, check the monitored interlock switch and monitor switch.

2. If the fuse F2 F8A is blown by incorrect door switching replace the defective switch(es) and the fuse F2 F8A.

3. If the fuse F2 F8A is blown, there could be shorts in the asymmetric rectifier or there is a ground in wire harness. A short in the asymmetric rectifier

may be occurred due to short or ground in H.V. rectifier, magnetron, high voltage transformer or H.V. wire. 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 the noise filter. Using an ohmmeter, check
between the terminals as described in the following table. 

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

CARRY OUT 4R CHECKS.

CARRY OUT 3D CHECKS.

Before carrying out the following tests make sure the heating element is cool completely. 

1. Resistance of heater.

Disconnect the wire leads to the heating element to be tested. Using ohmmeter with low resistance range. Check the resistance across the termi-
nals of the heating element as described in the following table.

Table: Thermal Cut-out Test

Parts Name

Temperature of “ON” condition 

(closed circuit)

Temperature of “OFF” condition 

(open circuit)

Indication of ohmmeter (When room 
temperature is approx. 20

C.)

Thermal cut-out TC1 145

C

Bellow -20

C

Above 145

C

Closed circuit

Thermal cut-out TC2, TC3

Bellow -20 or -35

C.

Above 170

C

Closed circuit

MEASURING POINT 

INDICATION OF OHMMETER

Between N and L 

Approx. 680 k



Between terminal N and WHITE 

Short circuit

Between terminal L and RED 

Short circuit

Table: Resistance of heater

Parts name

Resistance

Grill heating element

Approximately 46.5 ~ 51.1



Engine heating element

Approximately 58.0 ~ 62.9



F2: F8A

20A

WHT

RED

R1

R2

N

Cx

Cy

L

L

L

L (min) Cx ± 20% Cy ± 20%

R1

R2

1.0mH

0.22 uF

4700pF 10 M

680k