Maytag MHW9000YW0 Mode D'emploi page 14

FOR SERVICE TECHNICIAN'S USE ONLY
10. DC Supplies
• +5V DC is used to power IC's and
processors on the circuit boards. If +5 V DC
was missing, the washer would become
unresponsive. To verify +5V DC ± 5%,
measure voltage at UI7 pin 7 (GND) to pin 2
(+5V [Vcc]). (Red lead to Vcc.)
• +12V DC is used to actuate most of the
120V AC relays, triacs, and switches on the
CCU. If +12V DC was missing, the motors,
valves, and pumps would not turn on. To
verify +12V DC ± 5%, measure voltage
at UI7 pin 3 (–7V) to pin 2 (+5V [Vcc]).
(Red lead to Vcc.)
Troubleshooting: Refer to the wiring diagram
on page 26 when troubleshooting the DC
supplies. If +5 or +12 V DC 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 time until the component loading down
that supply has been identified.
11. Unplug washer or disconnect power.
12. Reassemble all parts and panels.
13. Perform the "Quick Diagnostic Test"
on page 6 to verify repairs.
Figure 12 - User Interface (Console, Modifier, and Center PCBs)
P13
Maytag
P13 (to Drum Light): See TEST #5: Drum Light, page 16.
Console
NOTE:
The User Interface (UI) must be replaced
as a single assembly. The UI includes the
Console, Modifier, and Center PCBs.
PAGE 14
P09
P08
Modifier
PCB
Pin 1: Drum_L_P
Pin 2: Open
Pin 3: Drum_L_N
TEST #2: User Interface (UI)
This test is performed when any of the
following situations occurs during the
UI Component Test (see page 7):
3 None of the indicators or LCD turn on
3 Some buttons do not light indicators
3 No beep sound is heard
None of the indicators or LCD turn on:
1. Unplug washer or disconnect power.
2. Remove the top panel to access the CCU & UI.
3. Visually check that all CCU connectors are
inserted all the way into the CCU. See Figure 11.
4. Remove console assembly. Be certain not to
pull on the wires between the console and CCU.
5. Visually check that all UI connectors are
inserted all the way into the UI. See Figure 12.
6. Visually check that the UI and housing
assembly is properly inserted into the front
console.
7. If all visual checks pass, perform
TEST #1: CCU Power Check, page 13,
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.
8. Reassemble all parts and panels.
P02 (to CCU): Pin 1: Standby
P06
Center PCB
P07
Modifier
P09
PCB
P13
P08
DO NOT REMOVE OR DESTROY
Pin 2: Ground
Pin 3: Data
Pin 4: Vcc (+5V)
Pin 5: Open
P02
Console Assembly
P02
P07
Center
PCB
P06
Whirlpool
Console