Daewoo KOR-137B Service Manual page 20

(TROUBLE 4) The following visual conditions indicate a probable defective touch control circuit
1. Incomplete segments
(1) Segments missing
(2) Partial segments missing
(3) Digit flickering other than normal display slight flickering
(4) :0 does not display when power is on.
2. A distinct change in the display is not on when it should be.
3. One or more digits in the display are not on when they should be.
4. Display indicates a number different from one touched.
5. Specific numbers (for example 2 or 3) will not display when the panel is touched.
6. Display does not count down or up with time cooking or clock operation.
7. Oven is programmable and cooks normally but no display shows.
8. Display obviously jumps in time while counting down.
9. Display counts down noticeably too fast while cooking.
10. Display does not show the time of day when the STOP/CLEAR pad is touched. (in case of setting the present time)
11. Oven lamp and turntable motor do not stop although cooking is finished. Check if the RELAY 2 contacts close.
If they close, replace P.C.B assembly.
CONDITION
Display does
not show
programming
at all, even if
keyboard is
pressed
NOTE
Before following the particular steps listed above in the troubleshooting guide for the failure of membrane
keyboard, please check for the continuity of each wire-harness between the membrane keyboard and P.C.B.
assembly.
CHECK
Check each pad for
continuity of the membrane
keyboard for the following
keyboard check procedure
RESULT
Normal
Abnormal
19
CAUSE
Replace the
Malfunction
of the control
circuit board
Replace the
Malfunction
of the membrane
keyboard
REMEDY
control
circuit board
membrane
keyboard