Service manual

R-3S68

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

COMPONENT TEST

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.

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 voltage is not applied to POWER Check supply voltage and oven main unit.

terminal of CPU connector (CN-A).

2 The rated voltage is applied to primary side Low voltage transformer or secondary circuit defective.

of low voltage transformer. 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)

RY2

RY1

(J1)

CN - A

D22

VRS1

LEAD

WIRE

LEAD WIRE

GREEN

POWER OL TTM

M PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING BOARD

(PWB) IS OPEN