Test #6: Pressure Switch - Whirlpool WFC8090GX Service Manual

COMPONENT TESTING
DANGER
Electrical Shock Hazard
Only authorized technicians should perform
diagnostic voltage measurements.
After performing voltage measurements,
disconnect power before servicing.
Failure to follow these instructions can result in
death or electrical shock.

TEST #6: Pressure Switch

This test checks the pressure switch, ACU, and wiring. NOTE:
Usually, if the pressure switch malfunctions, the washer will
generate a water level sensor error (F3E1).
1. Check the functionality of the water level sensor by
running a small load cycle. The valve should turn off
automatically after sensing the correct water level in
the tub. The following steps assume that this step was
unsuccessful.
2. Press START/PAUSE to stop the cycle and then press
POWER. The cycle will cancel and drain the water from
the tub.
3. Unplug washer/dryer or disconnect power.
4. Remove top panel to access tub, air trap, and pressure
hose connections. Pressure switch is located at top right
front of cabinet.
5. Check connections from tub to air trap, air trap to
pressure hose, and pressure hose to pressusre switch.
6. Check to ensure hose is routed correctly in the lower
cabinet and not pinched or crimped.
7. Verify there is no water, suds, or debris in the hose or air
trap. Disconnect hose from pressure switch, clean air trap
and remove and blow into hose to clear water, suds, or
debris.
PRESSURE SENSOR (APS)
PRESSURE SWITCH
3-10 Whirlpool Smart All-In-One Washer & Dryer
n
For Service Technician Use Only
ACU
J20-1
GND
J20-2
APS INPUT
J20-3
+5 VDC
Figure 2 - Pressure Switch
8. Check hose for leaks. Replace if needed.
9. Gently lay washer/dryer on its right side to access the
ACU. Remove AC shield and ACU cover.
10. Visually check that connector J20 is inserted all the way
into the ACU. Also check that the pressure switch harness
is securely connected to the switch.
11. Check the harness between the ACU and pressure switch
for continuity.
¾ If there is continuity, go to step 12.
¾ If there is no continuity, repair or replace as necessary.
12. Plug in washer/dryer or reconnect power.
13. With a voltmeter set to DC, connect black probe to ACU
connector J20, pin 1 (GND) and red probe to J20, pin 3
(+5V [Vcc]).
¾ If +5V DC is present, replace the pressure switch.
(Before replacing the switch, make sure that there is
NO water remaining in the tub or there will not be an
accurate water level measurement and an error code
may appear. Drain the tub by running a drain & spin
cycle with the switch plugged into J20 but with the
hose removed).
¾ If +5V DC is not present, perform TEST #1: ACU Power
Check on page 3-4.
14. If the preceding steps did not correct the problem, replace
the ACU.
¾ Unplug washer/dryer or disconnect power.
¾ Replace the ACU.
¾ Reassemble all parts and panels.
¾ Perform the Service Diagnostic Mode Tests on page 2-3
to verify repair.
Hose Connection
Figure 1 - Pressure Switch
PRESSURE SWITCH
3
GND
2 APS OUTPUT
1
+5 VDC
Harness
Connector