Kenwood KM3901T Service Manual page 8

4-3-5 Reassembly Test
After replacement of the defective component parts of the door, reassemble it and follow the instructions below for proper
installation and adjustment so as to prevent an excessive microwave leakage.
1. When mounting the door to the oven, be sure to adjust the door parallel to the bottom line of the oven
face plate by moving the upper hinge and lower hinge in the direction necessary for proper alignment.
2. Adjust so that the door has no play between the inner door surface and oven front surface. If the door
assembly is not mounted properly, microwave energy may leak from the space between the door and
oven.
3. Do the microwave leakage test.
4-4 Replacement of Fuse
1. Disconnect the oven from the power source.
2. Remove the 10A fuse in the fuse holder.
3. When replacing the 10A fuse, be sure to use an exact replacement part. If new 10A fuse blows out again
after replacement, check the primary interlock switch, door sensing switch and interlock monitor switch.
4. When the above three switches operate properly, check if any other part such as the control circuit board,
blower motor or high voltage transformer is defective.
4-5 Replacement of Drive Motor
1. Take out the glass tray, guide roller and coupler from
cavity.
2. Turn the oven upside down to replace the drive motor.
3. Remove a screw securing the drive motor cover.
4. Disconnect all the lead wires from the drive motor.
5. Remove screws securing the drive motor to the cavity.
6. Remove the drive motor.
7. When replacing the drive motor, be sure to remount it
in the correct position.
8. Connect all the leads to the drive motor.
9. Screw the deive motor cover to the base plate with a
screw driver.
10. Remount the coupler in the correct position.
4-6 Replacement of Ceramic Heater
1. Take out the outer panel
2. Disconnect the connectors from the heater ceramic
and wire leade.
3. Remove screws securing the bracket upper to the oven
cavity.
4. Remove one screw securing the bracket heater.
Screw
Drive Motor Cover
Screw
Bracket Upper
Screw
Disassembly and Reassembly
Drive Motor
Base Plate
Screw
ceramic
Heater
Bracket
Heater
4-3