Electrolux GLMB209DB Service Manual page 18

GLMB209DB
GLMB209DS
GLMB209DQ
PLMB209DC
PROCEDURE
LETTER
2.
2-1 In connection with pads.
2-2 In connection with indicators
2-3 Other possible problems caused by defective control unit.
3. If the Key unit or the Control unit is defective.
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) Replace the Control unit assembly.
5) Reconnect all leads removed from components during testing.
6) Re-install the outer case (cabinet).
7) Reconnect the power supply cord after the outer case is installed.
8) Run the oven and check all functions.
4. When testing is completed,
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) Reconnect all leads removed from components during testing.
5) Re-install the outer case (cabinet).
6) Reconnect the power supply cord after the outer case is installed.
7) Run the oven and check all functions.
J KEY UNIT TEST
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. Using an ohmmeter and referring to the key unit matrix indicated on the control unit circuit, check the
circuit between the pins of the key unit that correspond to the STOP/CLEAR pad. When the pad is
pressed, the ohmmeter should indicate short circuit. When the pad is released, the ohmmeter should
indicate open circuit. If incorrect readings are obtained, the key unit is faulty and must be replaced.
About the other pads, the above method may be used.
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
TEST PROCEDURES
Control Unit
The following symptoms indicate a defective control unit.
a) When touching the pads, a certain group of pads do not produce a signal.
b) When touching the pads, no pads produce a signal.
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
COMPONENT TEST
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