Whirlpool MVWC400XW Technical Education page 72

TROUBLESHOOTING GUIDE (continued)
FOR SERVICE TECHNICIANS ONLY
TROUBLESHOOTING TESTS
TEST #1: Main Control
This test checks for incoming and outgoing
power to and from main control. This test
assumes that proper voltage is present at
the outlet.
1. Unplug washer or disconnect power.
2. Remove console to access main control.
3. Check the AC power cord for continuity.
4. Verify that ALL connectors are inserted
all the way into the main control.
5. Plug in washer or reconnect power.
6. Is the "Diagnostic LED" ON or OFF?
ON: (+5VDC present) continue to step 8.
OFF: (+5VDC missing) proceed to step 7.
7. With a voltmeter set to DC, connect black
probe to J9-3 (Circuit Gnd) and red probe
to J9-1 (+5VDC).
If +5VDC is present, go to step 8.
If +5VDC is not present, go to step 9.
8. With a voltmeter set to DC, connect black
probe to J9-3 (Circuit Gnd) and red probe
to J9-8 (+13VDC).
If +13VDC (and +5VDC) are present, and
UI is unresponsive, go to Test #4: Console
and Indicators, page 16.
If +13VDC is not present, go to step 9.
9. Check if shifter assembly is affecting the
main control DC supplies.
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.
6-5
a. Unplug washer or disconnect power.
b. Remove connector J2 from main control.
c. Plug in washer or reconnect power.
d. Recheck the DC voltages per steps 7 & 8.
If the DC voltages return, replace shifter
assy.
If one or more DC voltages are still missing,
go to step 10.
10. Check if console UI is affecting the main
control DC supplies.
a. Unplug washer or disconnect power.
b. Remove connector J9 from main control.
c. Plug in washer or reconnect power.
d. Recheck the DC voltages per steps 7 & 8.
Perform voltage checks inside header J9
on the board – do not short pins together.
If the DC voltages return, replace console
UI.
If one or more DC voltages are still missing,
go to step 11.
11. Main Control has malfunctioned.
a. Unplug washer or disconnect power.
b. Replace the main control.
c. Reassemble all parts and panels.
d. Plug in washer or reconnect power. Calibrate
washer and perform Automatic Test to
verify repair.