[Microwave Repair] A collection of common troubleshooting experience in microwave ovens allows you to easily solve the failure
The start button on the touch control panel does not work after turning it on.
After inspection, it is found that the circuit of the key matrix is in poor contact, and the fault is solved after replacing the control panel.
Start normal work and stop automatically for 3 minutes when it is turned on.
It was checked that the thermal cut-out malfunctioned due to poor performance, and the fault was eliminated after replacing the thermal cut-out.
The oven is on fire when it is turned on to cook.
After inspection, it was found that there was too much oil residue in the furnace, which caused ignition. After removing the residual oil in the furnace, the fault was rectified.
Food is undercooked when cooking after power on.
After inspection, the aging function of the magnetron is degraded, and the fault is eliminated after replacing the magnetron. The other two machines have the same fault. After inspection, the high-voltage capacitor loses capacity and the high-voltage diode forward resistance increases. The fault is eliminated after replacing the high-voltage capacitor and high-voltage diode respectively.
The cooking time is too long after switching on.
After inspection, the mains voltage is too low, and the fault is eliminated after stabilizing the voltage with a high-power AC voltage stabilizer. Another machine has the same fault. After inspection, the magnetron choke coil is broken and the fault is eliminated after replacing the magnetron.
The display is normal but no microwave output after power on.
After inspection, the secondary coil of the high-voltage transformer is open circuit, and the fault is rectified after replacing the high-voltage transformer. The other two machines have the same fault. After inspection, the high-voltage capacitor is broken down and the high-voltage diode is burned out. After replacing the high-voltage capacitor and the high-voltage diode respectively, the fault is eliminated.
It works normally for half an hour and then shuts down.
After checking, the cooling fan does not rotate, and the temperature inside the box is too high. After replacing the fan, the fault is rectified. The other two machines have the same fault. After inspection, the damaged connection caused a short circuit and the inlet and exhaust pipes in the box were blocked by a small wooden stick. After connecting the connection and removing the blockage, the fault was eliminated.
Turn on the power and it shows normal, but it cannot heat food.
After inspection, it was found that RY1 could not be closed due to the short circuit of Q4. After replacing the 2SC1685 triode of the same model, the fault was eliminated. The other machine has the same fault. After inspection, the capacitor C23 is broken down, resulting in the over-current damage of Q4. Replace the same type of capacitor and the fault is eliminated after Q4.
The microwave doesn’t work and doesn’t display anything when turned on.
After inspection, the voltage regulator circuit ZD1 is broken down, resulting in the voltage drop of +18V, Q1 does not work, and +5V has no output. After replacing the ES3 Zener diode of the same type 5.6V, the fault is rectified.
Works fine when powered on but often burns food.
After inspection, it was found that the variable value of R27 caused the 3kΩ resistance and the fault was eliminated.
The cooking program is set after the power is turned on, and the microwave oven does not work.
After inspection, the steam sensor is damaged. After replacing the steam sensor of the same type, the fault is rectified.
Cannot keep warm after power on.
After inspection, the temperature sensor is faulty, and the fault is solved after replacing the same type of temperature sensor.
There is a spark in the oven while cooking after turning it on.
After inspection, the high-voltage line is close to the case, and the fault is solved after separating the high-voltage line. The other machine has the same fault. After inspection, it uses raw oil for cooking, and the raw oil contains moisture, which causes ignition at high temperature. Troubleshooting after cooking with cooked oil.
Frequently burnt food after switching on.
After inspection, the temperature sensor is faulty, and the fault is solved after replacing the temperature sensor.
The furnace light is on when it is turned on, but it does not heat up.
After inspection, the secondary winding of the high-voltage transformer is open, and the fault is rectified after replacing the high-voltage transformer. The other two machines have the same fault. After inspection, the RY1 coil of the relay is blown and the primary lead of the leakage inductance transformer is open. After replacing the high-voltage transformer and the same type of relay, the fault is eliminated.
The microwave does not work when turned on.
After inspection, the power lead is broken, and the fault is eliminated after connecting the lead. The other two machines have the same fault. After inspection, the low-voltage coil group of the transformer is burned out and the power delay device is damaged. The fault is eliminated after replacing the same type of transformer and power delay device respectively.
The word “88:88” will be displayed after 10 seconds under automatic cooking operation after power on.
After inspection, it was found that the digital program circuit was damaged, which caused the coil of the steam sensor to open circuit. After replacing the steam sensor, the fault was solved.
The microwave oven does not work when the automatic cooking function is set after power on.
After inspection, the steam sensor is damaged, and the fault is solved after replacing the steam sensor.
It will stop working ten minutes after it is turned on, and the display will display the words “88:88”.
After inspection, the steam sensor is damaged. After replacing the steam sensor of the same type, the fault is rectified.
The boot does not work and the monitor does not show.
After inspection, the varistor VRS1 is damaged, and the fault is eliminated after replacing the varistor of the same type.
There is no microwave output after power on, and food cannot be heated.
After inspection, the high-voltage diode of the microwave generating circuit was broken down, and the fault was eliminated after replacing the diode of the same type.
The food is often burnt after switching on.
The thermal switch contacts are sintered after inspection, and the problem is solved after removing the oxide layer with sandpaper.
The oven light is on after power on, but there is no microwave output.
After inspection, the door latch switch is in poor contact. After repairing the door latch switch, the fault is eliminated.
The stove light is on after switching on, but it takes a long time to cook food.
After inspection, the heating performance of the magnetron deteriorated due to aging, and the fault was eliminated after replacing the magnetron.
Turn on the power supply, the microwave oven does not work, and there is no display on the display.
After inspection, it was found that the varistor VRS1 was burnt out, which caused the primary short circuit of the transformer. After replacing the varistor of the same type, the fault was rectified.
The display does not light up after power on, and no response is made to pressing the touch keys.
After inspection, the b and e poles of the reset circuit Q1 were broken down, and the fault was eliminated after replacing the same type of A9335 tube.
There is a loud “humming” sound when the machine is turned on and the food cannot be cooked.
After inspection, the filament of the magnetron and the anode are short-circuited, which causes the working current of the leakage inductance transformer to be too large. After replacing the magnetron, the fault is eliminated.
The stove light is on after switching on, but food cannot be cooked.
After inspection, the high-voltage diode of the microwave generating circuit is open, and the fault is rectified after replacing the high-voltage diode of the same type.
There is no microwave output after power on, pressing the function key is invalid.
After inspection, the reset capacitor C3 was broken down, and the fault was eliminated after replacing the 47μF/16V electrolytic capacitor.
The timer, turntable, and stove lights are all normal after switching on, but the food cannot be heated.
After inspection, it was found that the high-voltage diode was short-circuited by the microwave, and the fault was eliminated after replacing it with two 1N4007 (1A/1000V) in series.
It works fine when powered on, but the buzzer doesn’t sound.
After inspection, the shunt resistor R30 of the buzzer circuit is short-circuited, and the fault is eliminated after replacing it with a 3?3kΩ resistor of the same type. The other two machines have the same fault. After inspection, the buzzer is damaged and the open circuit is open and the buzzer pushes the transistors Q30b and c. The fault is eliminated after replacing the buzzer and Q30 respectively.
The cooked food is undercooked after switching on.
After inspection, the magnetron is open, and the fault is solved after replacing the magnetron. The other two machines have the same fault. After inspection, the internal ignition of the magnetron and the aging heating performance of the magnetron have deteriorated. The fault was eliminated after replacing the magnetron respectively.
When the timer is set after power on, the fuse will blow immediately.
After inspection, it was found that the secondary of the high-voltage transformer was short-circuited, and the fault was rectified after replacing the high-voltage transformer of the same type. The other machine has the same fault. After inspection, the capacitor is broken down and the fault is eliminated after replacing the capacitor of the same specification.
Turn off the furnace door start switch after turning it on, and the fuse will blow immediately after it is turned on.
After inspection, the monitoring switch push rod of the furnace door interlocking mechanism was broken, and the fault was rectified after replacing the monitoring switch. The other machine has the same fault. After inspection, the turntable motor coil is short-circuited and the turntable motor is replaced. The fault is eliminated.
The food is often burnt after switching on.
The thermal switch contact is bad after inspection, and the fault is eliminated after repairing the contact.
The microwave oven stops working before the set time after it is turned on.
After inspection, the fan motor stops rotating and the magnetron is overheated, and the hot switch automatically disconnects the power supply. When the temperature reaches 135°C, the hot switch resets and the fault is eliminated. The other machine has the same fault. After inspection, the hot switch is damaged. After the hot switch is replaced, the fault is eliminated.
Declare: The above methods are derived from the program system index or shared by netizens. They are for your reference only and do not represent the research views of this website. sex and authority.
