Section 3 Troubleshooting and Testing
3-13
Procedure
Letter
O
Component Test
FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
To protect the electronic circuits, this model is provided with a
fi
ne foil pattern added to the primary
on the PWB, this foil pattern acts as a fuse.
Fuse check and repairs.
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. Follow the troubleshooting guide given below for repair.
8. Reconnect the power supply cord. Run the oven and check all functions.
Follow the troubleshooting guide given below, if indicator does not light up after above
check and repairs are
fi
nished.
1. Disconnect the power supply cord and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the leads to the primary of the power transformer. Ensure that these leads remain
isolated from other components and oven chassis by using insulation tape.
5. After that procedure, re-connect the power supply cord.
6. Follow the troubleshooting guide given below for repair.
7. Disconnect the power supply cord.
8. Open the door and block it open.
9. To discharge high voltage capacitor, wait for 60 seconds.
10. Reconnect all leads removed from components during testing.
11. Re-install the outer case (cabinet).
12. Reconnect the power supply cord after the outer case is installed.
13. Run the oven and check all functions.
STEPS
OCCURRENCE
CAUSE OR CORRECTION
1
The rated AC voltage is not present between Pin No. 3 of the 3-pin
connector (CN -C) and the lower side terminal of the relay RY-1
Check supply voltage and oven power cord.
2
The rated AC voltage is present at primary side of low voltage
transformer.
Low voltage transformer or secondary circuit defective.
Check and replace the control unit.
STEPS
OCCURRENCE
CAUSE OR CORRECTION
1
Only pattern at “a” is broken.
*Insert jumper wire J1 and solder.
2
Pattern at “a” and “b” are broken.
Replace the control unit.
5. Make a visual inspection of the varistor. Check
for burned damage and examine the transformer with
a tester for the presence of layer short-circuit (check
the primary coil resistance which is approximately
780
Ω
±10%). If any abnormal condition is detected,
replace the control unit.
6. Reconnect all leads removed from components during
testing.
7. Re-install the control unit to the control panel and
re-install the control panel to the oven.
Summary of Contents for CGMV173KB
Page 2: ......
Page 14: ...Section 2 Operation 2 2 Figure 2 1 Oven Off Condition Figure 2 2 Oven ON Cooking Condition ...
Page 51: ...Section 5 Wiring Diagrams 5 1 Wiring Schematic Oven ON Condition ...
Page 52: ...Section 5 Wiring Diagrams 5 2 Pictorial Component Diagram ...
Page 54: ...Section 5 Wiring Diagrams 5 4 LD1 LD2 LD3 LD4 LD5 Control Board ...
