5-8
FOR SERVICE TECHNICIAN’S USE ONLY
COMPONENT TESTING (continued)
10. DC Supplies
•
+5VDC is used to power IC’s and
processors on the circuit boards. If +5 VDC
was missing, the washer would become
unresponsive. To 5VDC ± 5%,
measure voltage at
UI7 pin 7 (GND) to pin 2
(+5V [Vcc]). (Red lead to Vcc.)
•
+12VDC is used to actuate most of the
120VAC relays, triacs, and switches on the
CCU. If +12VDC was missing, the motors,
valves, and pumps would not turn on. To
12VDC ± 5%, measure voltage
at UI7 pin 3 (–7V) to pin 2 (+5V [Vcc]).
(Red lead to Vcc.)
Troubleshoong:
Refer to the wiring diagrams
on pages 23–24 when troubleshoong the
DC supplies. If +5 or +12 VDC is missing on
the CCU, unplug washer or disconnect power,
and then disconnect all components from the
CCU relying on that supply. Plug in washer or
reconnect power and check if the DC supply
has returned. If not, replace the CCU. If it has,
turn washer off and reconnect one connector
at a me unl the component loading down
that supply has been idenfied.
11. Unplug washer or disconnect power.
12. Reassemble all parts and panels.
13. Perform the “Quick Diagnosc Test”
to verify repairs.
TEST #2: User Interface (UI)
This test is performed when any of the
following situaons occurs during the
User Interface Test:
�
None of the indicators or display turn on
�
Some buons do not light indicators
�
No beep sound is heard
None of the indicators or display turn on:
1. Unplug washer or disconnect power.
2. Remove the top panel to access the CCU
and user interface (UI).
3. Visually check that ALL CCU connectors
are inserted all the way into the CCU.
4. Visually check that ALL UI connectors
are inserted all the way into the UI.
5. Visually check that the UI and housing
assembly is properly inserted into the front
console.
6. If all visual checks pass, perform TEST #1: CCU
Power Check, to verify supply voltages.
�
If supply voltages are present, replace the
user interface and housing assembly.
�
If supply voltages are not present, replace
the CCU.
7. Reassemble all parts and panels.
8. Plug in washer or reconnect power.
9. Perform the “User Interface Test”
to verify repair.
Some buons do not light indicators:
1. Unplug washer or disconnect power.
2. Remove the top panel to access the CCU
and user interface (UI).
3. Visually check that the UI and housing
assembly is properly inserted into the front
console.
4. If visual check passes, replace the UI and
housing assembly.
5. Reassemble all parts and panels.
6. Plug in washer or reconnect power.
7. Perform the “User Interface Test”
to verify repair.
No beep sound is heard:
1. Unplug washer or disconnect power.
2. Remove the top panel to access the CCU
and user interface (UI).
3. Visually check that ALL CCU connectors
are inserted all the way into the CCU.
4. Visually check that ALL UI connectors
are inserted all the way into the UI.
5. If all visual checks pass, replace the UI
and housing assembly.
6. Perform the “User Interface Test”
to verify repair.
TEST #3: Motor Circuit
This test checks the motor, motor control unit
(MCU), and wiring.
From CCU MI3
(MCU Communicaons)
From CCU MS2
(MCU Power)
To Motor
Figure 4 - Motor Control Unit (MCU)
Summary of Contents for WFW94HEX Series
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Page 76: ...5 17 NOTES ...
Page 83: ...7 1 WIRING DIAGRAMS WASHER NON STEAM ...
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