R-4G75M (serv.man3). Section 2 Test procedures, LSI table (page 8-22) - Sharp Home Appliance Service Manual (repair manual). Page 8

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Checking the initial sensor cooking condition
(1) The oven should be plugged in at least five minutes before sensor cooking.
(2) Room temperature should not exceed 95˚F(35˚C).
(3) The unit should not be installed in any area where heat and steam are generated. The unit should not

be installed, for example, next to a conventional surface unit. Refer to the "INSTALLATION Instructions"
.

(4) Exhaust vents are provided on the back of the unit for proper cooling and air flow in the cavity. To permit

adequate ventilation, be sure to install so as not to block these vents. There should be some space for
air circulation.

(5) Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off any moisture

with a dry cloth or paper towel.

(6) The Sensor works with food at normal storage temperature.For example, chicken pieces would be at

refrigerator temperature and canned soup at room temperature.

(7) Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings. The sensor

will detect the vapor given of by the spray and turn off before food is properly cooked.

(8) After 25 minutes if the sensor has not detected the vapor of the food, ERROR will appear and the oven

will shut off.

Water load cooking test
Make sure the oven has been plugged in at least five minutes before checking sensor cook operation. The
cabinet should be installed and screws tightened.
(1) Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.
(2) Place the container on the center of tray in the oven cavity.
(3) Close the door.

To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on
the PWB, this foil pattern acts as a fuse. If the foil pattern is open, follow the troubleshooting guide
given below for repair.

Problem: POWER ON, indicator does not light up.

CARRY OUT 3D CHECKS

STEPS

OCCURANCE

CAUSE OR CORRECTION

  1

The rated AC voltage is not present at 

POWER terminal of CPU connector (CN-A)

Check supply voltage and oven power cord. Please use 

term "Low voltage transformer" when refering to 

transformer T1

  2 

The rated AC voltage is present at primary 

side of  low voltage transformer.

Low voltage transformer or secondary circuit  defective. 

Check and repair.

  3

Only pattern at "a" is broken.

*Insert jumper wire J1 and solder. (CARRY OUT 3D 

CHECKS BEFORE REPAIR)

  4

Pattern at "a" and "b" are broken.

*Insert the coil RCILF2003YAZZ between "c" and "d". 

(CARRY OUT 3D CHECKS BEFORE REPAIR) 

NOTE: At the time of these repairs, make a visual

inspection 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.

CARRY OUT 4R CHECKS

OL TTM FAN M

POWER

CN–A

(J1)

VRS1

RY1

D81

(R110)(J11)

(J10)

D82

RY2

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1

3

5