Troubleshooting Guide - Panasonic NE-3280 Service Manual

NE-3280 / NE-2180 / NE-2180C

15 TROUBLESHOOTING GUIDE

1. Check grounding before checking for trouble.
2. Be careful of the high voltage circuit.
3. Discharge high voltage capacitor.
4. When checking the continuity of the switches or the high voltage transformer, disconnect one lead wire from these parts and then check
continuity with the AC plug removed. To do otherwise may result in a false reading or damage to your meter.
When disconnecting a plastic connector from a terminal, you must hold the plastic connector instead of the lead wire and then disconnect it,
otherwise lead wire may be open or the connector cannot be removed.
5. Be sure to ground any static electric charge built up in your body, before handling the D.P.C.
6. A 208-230V AC is present at the shaded area ( ) of the power supply circuit board (Terminals of power relays and primary circuit of low voltage
transformer). When troubleshooting, be cautious of possible electrical shock hazard.
First of all operate the microwave oven following the correct operating procedures described on pages 4 of this service manual in
order to find the exact cause of any trouble.
NOTE:
If the unit shows faulty symptom as shown below, check the parts listed in possible cause column depending on
failure indication e.g. F81, F82 in the display.
[TROUBLE] Oven does not operate at all or oven does not start cooking. NE-3280
DISPLAY
F33 Open temperature
sensor (exhaust)
F34 Short temperature
sensor (exhaust)
F44
F01 Exhaust temperature
(With continuous exceeds 120°C
beep sounds)
F03 Input voltage exceed
+ 12.5%
F04 Input voltage is less
than — 12.5%
F05 Memory failure
No display 1.25A fuse blown
No display 1.25A fuse is OK
F81 No voltage supply to
high voltage trans.
(lower/left)
F82 No voltage supply to
high voltage trans.
(lower/right)
F83 No voltage supply to
high voltage trans.
(upper/left)
F84 No voltage supply to
high voltage trans.
(upper/right)
F86 Shorted contacts of RY-
3
F87 Shorted contacts of RY-
5
F88 Shorted contacts of RY-
7
CONDITIONS
1. Temperature sensor failure
2. Digital programmer circuit failure
3. Loose connector CN5
1. Temperature sensor failure
2. Digital programmer circuit failure
1. Shorted membrane switch
1. Burning food in the oven due to over cook
1. Increase in power source voltage
1. Decrease in power source voltage
1. Digital programmer circuit failure
1. Low-Voltage transformer failure
1. Thermal cutout failure
2. Low voltage transformer failure
3. Digital programmer circuit failure
1. Relay failure RY-3 (A)
2. Loose connector CN256, CN257
3. Digital programmer circuit failure
1. Relay failure RY-5 (B)
2. Loose connector CN258, CN259
3. Digital programmer circuit failure
1. Relay failure RY-7 (C)
Loose connector CN260, CN261
2. Digital programmer circuit failure
1. Relay failure RY-9 (C)
Loose connector CN262, CN263
2. Digital programmer circuit failure
1. Relay failure RY-3 (A)
2. Digital programmer circuit failure
1. Relay failure RY-5 (B)
2. Digital programmer circuit failure
1. Relay failure RY-7 (C)
2. Digital programmer circuit failure
CAUTION
POSSIBLE CAUSE
26
TIMING OF FAILURE INDICATION
It is appeared when failure occured.
It is appeared when failure occured.
It is appeared 2 minutes after failure
occured.
It is appeared when exhaust temperature
exceeds above 120°C.
It is appeared when the unit is plugged in.
Note that it returns normal operation mode
by tapping the STOP pad.
It is appeared when the unit is plugged in.
Note that it returns normal operation mode
by tapping the STOP pad.
It is appeared when failure occured.
It is appeared when failure occured.
It is appeared when failure occured.
It is appeared when failure occured.
It is appeared when failure occured.
It is appeared when failure occured.
It is appeared when failure occured.