Inverters - Whirlpool MH9180XL Service Manual

INVERTERS

MEASURING OVEN INPUT CURRENT
1. Remove the screw from the power cord
retaining plate and remove the plate.
2. Pull the power cord out of the cabinet and
separate the wires.
3. Connect an ammeter clamp around the
white power cord wire.
Ammeter Clamp Around
White Power Cord Wire
Power Cord
Power Cord
Retaining Plate
4. Turn the microwave oven On.
5. Check the ammeter for a 15A reading.
• If the ammeter indicates more than 0.5
amps, check the magnetron and its
wiring.
• If the ammeter indicates less than 0.5
amps, it indicates that there is no input
to the 1100 W inverter. Check for the
following:
- No AC voltage supply or control sig-
nal. Check the control power supply
board at the relay terminals for 120
VAC (see the photos at the top of the
next column).
Relay
WARNING
Electrical Shock Hazard
Disconnect power before servicing.
Replace all parts and panels before
operating.
Failure to do so can result in death or
electrical shock.
1100 W INVERTER
Refer to page 4-20 for the procedure for servic-
ing the 1100 W inverter.
IMPORTANT: HIGH VOLTAGE—DO NOT
MEASURE!
5-8
Control Power
Supply Board
Test Leads