Troubleshooting - Samsung M735 Service Manual

6. Troubleshooting

4000 VOLTS EXIST AT THE HIGH VOLTAGE AREA. DO NOT OPERATE THE OVEN WITH CABINET PARTS REMOVED. DO NOT
REMOVE THE CABINET PARTS IF THE POWER SUPPLY CORD IS PLUGGED IN THE WALL OUTLET. UNPLUG THE POWER CORD
BEFORE SERVICING.
6-1 Electrical Malfunction
Parts Cause
Fuse blows Defective primary
out when interlock switch
door is ary winding.
opened.
Defective interlock
monitor switch
Fuse is Layer short of the
open. secondary coil of
H. V. Transformer
1) Fuse blown out
2) Poor contact of
power cord
3) Defective lamp
Oven lamp 4) Defective timer
does not contacts
light.
5) Thermal cutout
S/W open
1) Defective
Fan does fan motor.
not operate.
2) Defective con-
tacts of timer
NOTE: Interlock monitor switch must be replaced when the fuse is blown out.
Samsung Electronics
WARNING FOR HIGH VOLTAGE
Diagnosis
Check continuity of the primary switch terminals with
wire removed using a multimeter. If there is continuity
between switch terminals when door is opened,
the switch is defective.
Check continuity of the monitor switch terminals
with wire removed by using a multimeter.
If there is continuity between switch terminals
when the door is closed, the switch is defective.
The fuse will not blow right away, but if it blows in a
few seconds, then there is a layer short.
If the fuse blows with H. V. Trans secondary open, the
transformer may be faulty.
Check fuse.
Check continuity of power supply cord. Also check
whether the power cord is securely wired.
The fan motor rotates, but lamp does not light.
Check the terminals of timer for continuity,
turning the timer knob ON and OFF repeatedly.
In this case the oven lamp and fan do not
turn on
If 220~230V is found at motor terminals, the motor
should be replaced.
The oven lamp does not light and fan motor
does not operate.
Remedy
Replace the primary
interlock switch
Replace the interlock
monitor switch
Replace H. V. Transformer
Replace the fuse.
Adjust or replace the
power supply cord.
Replace the lamp.
Replace the timer.
Replace the
thermal cutout S/W
Replace the motor.
Replace the timer.
6-1