Sharp R-330H, Service Manual

Page: 13 / 36

R-330H
11
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
Table: Resistance of Motor
Motors Resistance
Fan motor Approximately 250
Ω
Turntable motor Approximately 14.5 k
Ω
If incorrect readings are obtained, replace the motor.
CARRY OUT 4R CHECKS
CARRY OUT 3D CHECKS.
1. If the fuse F10A is blown, there could be shorts or ground in electrical parts or wire harness.
Check them and replace the defective parts or repair the wire harness.
2. If the fuse F10A is blown when the door is opened, check the 1st. latch switch, 2nd. interlock relay
and monitor switch.
If the fuse F10A is blown by incorrect door switching replace the defective switch(s) and the fuse
F10A.
CARRY OUT 4R CHECKS.
CAUTION: ONLY REPLACE FUSE F10A WITH THE CORRECT VALUE REPLACEMENT
H BLOWN FUSE F10A
I NOISE FILTER TEST
CARRY OUT 3D CHECKS.
Disconnect the leads from the terminals of the noise
filter. Using an ohmmeter, check between the termi-
nals as described in the following table.
MEASURING POINT
INDICATION OF
OHMMETER
Between N and L Open circuit
Between terminal N and WHITE Short circuit
Between terminal L and RED Short circuit
If incorrect readings are obtained, replace the noise filter unit.
CARRY OUT 4R CHECKS.
CARRY OUT 3D CHECKS.
If the high voltage fuse is blown, there could be a short in the high voltage rectifier or the magnetron.
Check them and replace the defective parts and high voltage fuse.
CARRY OUT 4R CHECKS.
CAUTION: ONLY REPLACE THE HIGH VOLTAGE FUSE WITH THE CORRECT VALUE RE-
PLACEMENT
J HIGH VOLTAGE FUSE TEST
K TOUCH CONTROL PANEL ASSEMBLY TEST
The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore,
unlike conventional microwave ovens, proper maintenance cannot be performed with only a
voltmeter and ohmmeter. In this service manual, the touch control panel assembly is divided into two
units, Control Unit and Key Unit, and also the Control Unit is divided into two units, CPU Unit and
Power Unit, and troubleshooting by unit replacement is described according to the symptoms
indicated.
RED
WHT
FUSE
F10A
N
L
LINE CROSS CAPACITOR
0.068
µ
/AC250V
NOISE SUPPRESSION COIL
LINE BYPASS CAPACITOR 0.0022
µ
/AC250V
LINE BYPASS CAPACITOR 0.0022
µ
/AC250V