Frigidaire CGMV173KB Servicing page 33

Procedure
Letter
FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
O
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.
STEPS
1
2
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
780Ω±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.
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.
STEPS
1
2
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.
OCCURRENCE
Only pattern at "a" is broken.
Pattern at "a" and "b" are broken. Replace the control unit.
OCCURRENCE
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
The rated AC voltage is present at primary side of low voltage
transformer.
Section 3 Troubleshooting and Testing
Component Test
CAUSE OR CORRECTION
*Insert jumper wire J1 and solder.
Check supply voltage and oven power cord.
Low voltage transformer or secondary circuit defective.
Check and replace the control unit.
CAUSE OR CORRECTION
3-13