Display blinks and jumps around after cookong time is completed

A convection microwave is a combination of a standard microwave oven and a convection oven. It allows food cooked in the convection microwave to be cooked quickly, yet come out browned or crisped as in a convection oven. However, most cakes cannot be baked in a microwave oven - only those without an open grain structure, such as brownies. There are microwaves which contain electric browning baking elements. A true convection microwave has a high velocity forced air fan to circulate the hot air uniformly.

more about Convection microwave

please follow this steps and fix it. God bless you

1. Main control board If the display on your microwave has gone out completely this is usually a sign that it is a malfunctioned main control board. To correct the issue the main control board would need to be replaced.
   
2. Display board A display board can either malfunction completely or partially, causing two separate results. If the display on the unit has completely gone out, this can be attributed to either a bad main control board or display board. On the other hand, if the display has only partially gone out, this is usually a sign that the display board is defective and will need to be replaced
   

1. Touch the CLOCK pad. This will activate the 12-hour system. (To activate 24-hour system, tap once more)
2. Enter the correct time of day by touching the time set panels.
3. Touch CLOCK pad.

You will know that you're changing the time when your display stops blinking and and the colon starts blinking.
If you have any other questions regarding your Daewoo KOR-630A, I located an online manual for you.
Cheers!
http://dl.owneriq.net/6/64d0773e-ca06-4c23-97b1-e039cfc523aa.pdf

The hi voltage transformer or the magnetron tube has gone bad. It's repairable but costly.

The owner's manual is here. On page 10 we find:

COOKING IN ONE STAGE
1. Press the POWER button; the Microwave and High
Cook indicators will light and “PL 10” will light in the
display.
2. Press the POWER button different times to set the
desired power; the display will show the percentage
you chose. If selecting power level 70%-10%, the
Low Cook indicator will light instead of the High
Cook indicator.
3. Press number keys to set the desired cooking time.
OPERATION(CONTINUED)
4. Press the START/+30SEC. button to start cooking;
the Microwave and one of the Cook indicators will
blink and the display will countdown the remaining
cooking time in minutes and seconds. It will beep
five times when cooking is completed.

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by unplugging the m/w for a few minutes and then replugging the problem is gone.

plse mention make and model Number

This is a common problem. i havent completly solved it yet but this helps.


Be very careful doing this, There is Voltages with AMPERAGES high enough to boil your blood inside a microwave.

I had mine apart cleaning it. Only one number worked on my display. I wiggled and messed around with the wires in the back of the display. And almost every number in the display works again. Hope this helps.

You can download your owner's manual free here.

From the manual:

SETTING THE CLOCK - When the microwave oven is plugged into an outlet, the oven will display " 0:00 "

1. Press the CLOCK button; the hour digit will blink
and the clock indicator will light.

2. Press the number keys to set current hour.

3. Press the number keys to set current minute.

4. Press AM/PM to choose AM or PM.

5. Press the CLOCK button again; the display will
show the present time. After the clock has been
set, the time will appear with blinking colon,
unless the oven is cooking or defrosting.

NOTES:

- To reset the present time in the display window when the oven is off, press the CLOCK button and
reset.

- If you make a mistake when setting the time, press the STOP/CLEAR button.

- To recall the actual time while the oven is cooking or defrosting, simply press the CLOCK button
and the display will show the actual time for three seconds.

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