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14
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
J
BLOWN FUSE 15A
I
NOISE FILTER TEST
CARRY OUT 3D CHECKS.
Disconnect the leads from the terminals of noise filter.
Using an ohmmeter, check between the terminals as
described in the following table.
Using an ohmmeter, check between the terminals as
described in the following table.
CARRY OUT 3D CHECKS.
If the fuse15A is blown, there is a shorts or grounds in electrical parts or wire harness. Check them and
replace the defective parts or repair the wire harness.
replace the defective parts or repair the wire harness.
CARRY OUT 4R CHECKS.
CAUTION:
Only replace fuse
with
the correct value replacement.
K
BLOWN FUSE F8A
CARRY OUT 3D CHECKS.
1. If the fuse F8A is blown when the door is opened, check the monitored latch switch and monitor
switch.
2. If the fuseF8A is blown by incorrect door switching replace the defective switch(es) and the fuse
F8A.
3. If the fuse F8A is blown, there could be shorts in the asymmetric rectifier or there is a ground in wire
harness. A short in the asymmetric rectifier may be occurred due to short or ground in H.V. rectifier,
magnetron, high voltage transformer or H.V. wire. Check them and replace the defective parts or
repair the wire harness.
magnetron, high voltage transformer or H.V. wire. Check them and replace the defective parts or
repair the wire harness.
CARRY OUT 4R CHECKS.
CAUTION:
Only replace fuse
F8A
with the correct value replacement.
F8A
15A
WHT
RED
R1
R2
N
Cx
Cy
L
L
L
L
GRILL HEATING ELEMENT (TOP) AND BOTTOM HEATING ELEMENTS TEST
MEASURING POINTS
INDICATION OF OHMMETER
Between N and L
Approx. 680 k
Ω
Between terminal N and WHITE
Short circuit
Between terminal L and RED
Short circuit
If incorrect readings are absorbed, replace the noise filter unit.
CARRY OUT 4R CHECKS.
L (min)
Cx
±
20%
Cy
±
20%
R1
R2
1.0mH
0.22
µ
F
4700pF
10 M
Ω
680k
Ω
CARRY OUT 3D CHECKS.
Before carrying out the following tests make sure the heating element is cool completely.
1. Resistance of heating element.
Disconnect the wire leads to the heating element to be tested. Using ohmmeter with low resistance
range. Check the resistance across the terminals of the heating element as described in the
following table.
range. Check the resistance across the terminals of the heating element as described in the
following table.
Table: Resistance of heating element
Parts name
Resistance
Grill heating element (top)
Approximately 61
Ω
Bottom heating element
Approximately 115
Ω
2. Insulation resistance.
Disconnect the wire leads to the heating element to be tested. Check the insulation resistance
between the element terminal and cavity using a 500V - 100M
between the element terminal and cavity using a 500V - 100M
Ω
insulation tester. The insulation
resistance should be more than 10 M
Ω
in the cold start.
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