Maytag MHW9000YW0 Mode D'emploi page 21

FOR SERVICE TECHNICIAN'S USE ONLY
TEST #13: Expansion Board (EB) Power Check
n Communicates with the Central Control Unit (CCU).
n Receives 120V AC, +5 (Vcc) and –7V DC from the CCU. (+12V [–7V to Vcc]).
n Detects the presence of the detergent cartridge and the level of detergent within.
n Controls the pump to dispense detergent determined by the wash cycle.
n Controls the diverter valve assembly (select models only).
TOP
VIEW
Diverter Valve Ass'y
(select models only)
SIDE
VIEW
EBP3-Expansion Board Power
Figure 15 - Expansion Board (EB)
This test checks for incoming power to the
Expansion Board (EB). This test assumes
that proper voltage is present at the CCU
(see TEST #1, page 13).
1. Unplug washer or disconnect power.
2. Remove top panel to access the machine
electronics.
3. Visually check that all connections to the
CCU and EB are fully inserted.
4. If visual check passes, continue to step 5.
5. Plug in washer or reconnect power.
IMPORTANT: Make sure door is closed and
verify detergent cartridge is inserted into drawer.
NOTE: Line voltage to and from the EB can
only be measured when the detergent pump
is actuated. This occurs for approximately
1-5 seconds toward the end of the FILL cycle
and also during the Quick Diagnostic Test.
DO NOT REMOVE OR
DEP2-Detergent Pump
DV2-Spray Valve
SOP2-Dispenser Valve
CIN4-Data In
DESTROY
DPS2-Detergent
Presence Sensor
Connect voltmeter as specified below. Verify
detergent cartridge is inserted into dispenser
drawer. Run the Quick Diagnostic Test and
watch for line voltage during the "C00" phase.
6. With a voltmeter set to AC, check for input
line voltage to the EB across pins 1 and 2 of
connector LPS2. (See NOTE at left.)
 If line voltage is present, continue to step 8.
 If line voltage is not present, go to step 7.
7. With a voltmeter set to AC, check for output
line voltage from the CCU across pins 1 and 2
of connector HSG2. (See NOTE at left.)
 If line voltage is present, check harnesses
and connections between the CCU and EB.
Repair as necessary.
 If line voltage is not present, go to TEST
#1: CCU Power Check on page 13.
Left
Locking
Tab
LPS2-AC In
Right
Locking
Tab
•
= pin-1
DLS3-Detergent
Level Sensor
PAGE 21