Cove DW2450 User manual

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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
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ErrorCodesandTroubleshooting
SERVICE MODE
Service mode allows a technician to review various user
settings/offsets, manually activate and deactivate
components, and monitor the unit's performance including
logged errors. In Service mode:
Bluetooth pairing PIN messaging, Wi-Fi control via
the Sub-Zero Group Owner’s App, error detection
and management, and diverter valve movement are
allowed.
Pressure-based drain pump control is active.
Standby Power mode, Smart Grid requests, wash
cycles, or monitoring of any analog I/O are not
allowed.
When the sump fills, it always fills to the volume of
"Main Wash #1" in the NORMAL wash cycle.
Service mode may be activated from the UIM panel, or via
the RS-485 connection using the Connected Diagnostics
program.
Service mode exits after 5 minutes with no input.
ENTER SERVICE MODE
Touch and hold Auto and Heavy for 5 seconds or
more.
Release Heavy, and continue to hold Auto for 5
seconds.
"Service Mode:" appears on the UIM.
SERVICE MODE FUNCTIONS
Service mode allows two main functions:
Use the Cancel key to scroll through the error codes.
Manually turn on and turn off components and
systems to confirm operation. Pressing a UIM key
turns on the corresponding component or system;
pressing the key again turns it off. Only one
component or system can be turned on at a time.
UIM KEY FUNCTIONS IN SERVICE MODE
UIM KEY CONTROL DISPLAY
Auto Toggles drain pump ON/OFF
(up to 50 secs. max. ON time). MOT4 (Drain pump motor)
Normal Toggles water inlet valve ON/
OFF. SOL1 (Water inlet valve)
Heavy Toggles wash pump ON/OFF. MOT1 (Wash pump
motor)
Quick Toggles heater ON/OFF (up to
70º C). HTR1 (Tub heating element)
Cycles+ Sets diverter valve position (at
each key press, diverter valve
changes its position). The door
must be shut for 15-45 seconds
to show a position change on
the UIM.
MOT2 (Diverter valve
motor), SV =
requested position,
PV = current position
(0 = Home, 1 =
Middle/Upper, 2 = All,
3 = Lower)
Options Toggles drying fan ON/OFF. MOT3 (Drying fan
motor)
Enter Toggles water softener
regeneration valve ON/OFF (if
applicable).
SOL2 (Water
softener regeneration
valve)
Cancel Toggles through any and all
stored error codes.
Also, touch and hold to exit
Service mode.
Error log table
Start Toggles dispenser coil ON/OFF
(300 ms ON, then OFF is the
only action).
SOL3 (Dispenser
coil)
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
FAULT-LEVEL ERROR CODES
Fault-level errors involve safety concerns, or indicate that
the dishwasher is inoperable. Only repairing the actual
fault will cancel a fault-level error. It will continue to appear
in the unit's error code list until the fault is repaired.
When a fault-level error occurs:
Any active functions, such as active wash cycles or
UIM navigation, are exited.
No user control of the unit is allowed, either by the
UIM interaction or by the Sub-Zero Group Owner's
App.
There may be an indication that a service call is
required via a UIM message and tone or in the Sub-
Zero Group Owner's App.
WARNING-LEVEL ERROR CODES
Warning-level errors are not safety-related or catastrophic.
They indicate that improper functionality of the unit may
occur, such as poor wash performance. A warning-level
error can be canceled in Service mode, but the error may
reappear if the condition that caused the error still exists.
When a warning-level error occurs:
The unit stays operable by the user, either by direct
UIM interaction or by the Sub-Zero Group Owner's
App.
An indication of the error may appear on the UIM
when the door is open.
CLEAR ALL ERROR CODES
From the UIM, exit Service mode (touch and hold the
Cancel key).
Use the User Setup menu's "Reset All" function.
TIP: It is also possible to clear all error codes by
clearing the error log table in the Connected
Diagnostics Program.
CLEAR INDIVIDUAL ERROR CODES
From the UIM:
Enter Service mode.
Touch the Cancel key to scroll through any error
codes.
Warning-level error codes will be cleared upon
each touch.
Fault-level error codes need to be repaired first.
Some error codes automatically clear
when they are repaired.
Some error codes require cycling power
to the unit.
Some error codes require using "Reset
All" in the User Options menu.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
DW2450 AND DW2450WS ERROR CODE TABLE
ERROR CODE TABLE
IMPORTANT NOTE: The table's error codes contain links to Answer Advisor articles. Click the error code number in
the table for the most up-to-date information about the error code.
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
050100 Fault MCM did not detect current
from MOT1 Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Replace the MCM assembly.
050103 Fault MCM incorrectly converted
current from MOT1 Replace the MCM assembly.
050104 Fault MCM damaged after MOT1
current exceeded 2.54 A Replace the MCM assembly.
050113 Fault MOT1 operated with open
phase (0 A) for 10 s Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Replace the MCM assembly.
050116 Fault MOT1 overloaded from
dishwasher environment Use Connected Diagnostics Program to monitor wash pump current for multiple
starts and stops of the wash pump motor during a wash cycle.
Check for a blockage inside the wash pump.
Test for proper operation with a Rinse/Hold cycle.
050117 Warning Input voltage under 190 V. If possible, check the quality of power delivered to the unit, including poor power
connection or damage to the power cord.
Test for proper operation with a Rinse/Hold cycle.
Replace the MCM assembly.
050118 Warning Input voltage over 400 V Replace the MCM assembly.
050119 Fault MCM incorrectly converted
thermistor input from AE1 Replace the MCM assembly.
050123 Warning MOT1 overloaded from
dishwasher environment and
MCM reached 212°F (100°C)
Let the unit cool down and test for proper operation with a Rinse/Hold cycle.
Replace the wash pump motor.
Replace the MCM assembly.
050124 Warning Input voltage loss of 50 V within
100 ms If possible, check quality of power delivered to the unit, including poor power
connection or damage to the power cord.
Test for proper operation with a Rinse/Hold cycle.
Replace the MCM assembly.
050126 Fault MCM read input voltage as 0 V
for 2 s Replace the MCM assembly.
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
050127 Warning MCM potentially damaged after
MOT1 current exceeded 2.54 A Replace the MCM assembly.
050135 Fault MOT1 overloaded from
dishwasher environment and
cycling MOT1 to max speed for
10 consecutive trials failed.
Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Use Connected Diagnostics Program to monitor wash pump current for multiple
start/stops of the wash pump motor during a wash cycle.
Check for a blockage inside the wash pump.
Test for proper operation using a Rinse/Hold cycle.
050136 Warning MOT1 overloaded from
dishwasher environment with
current over 800 mA
Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Use Connected Diagnostics Program to monitor the wash pump current for the
wash pump motor amperage exceeding 800 mA during a wash cycle.
Check for a blockage inside the wash pump.
Test for proper operation using a Rinse/Hold cycle.
050138 Fault No communication between
MCM and MOT1 for 30 s Replace the MCM assembly.
050139 Fault MOT1 overloaded from
dishwasher environment and
reached 284°F (140°C) for 2
consecutive trials
Let the unit cool down and test for proper operation with a Rinse/Hold cycle.
Check for a blockage inside the wash pump.
Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Replace the MCM assembly.
050140 Fault MCM detected an overcurrent
condition during MOT1 steady
speeds for 10 consecutive trials
Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Replace the wash pump motor.
Replace the MCM assembly.
050144 Warning MOT1 overloaded from
dishwasher environment and
reached 284°F (140°C)
Let the unit cool down and test for proper operation with a Rinse/Hold cycle.
Check for a blockage inside the wash pump.
Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Replace the MCM assembly.
050180 Warning MOT1 did not receive speed set
point from the MCM in 80 ms Replace the MCM assembly.
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
050186 Fault Water flow problem Verify the water supply is on.
Verify there are no kinks in the water supply line.
050187 Fault Water flow problem Verify the water supply is on.
Verify there are no kinks in the water supply line.
050199 Fault MCM did not detect MOT1 stop
command for 10 seconds while
PWM stopped, or MCM
detected a fault while inverter
powered
Confirm the wash pump wire harness connections are tight and continuity of the
circuit, including across connector PJ26.
Measure the resistance of all three phases of the wash pump (60.0 Ω± 3.0 Ω).
Replace the MCM assembly.
100147 Fault MCM did not detect voltage
within valid limits from AE1 for
300 s
Confirm the temperature and turbidity sensor wire harness connections are tight
and continuity of the circuit, including across connector PJ9.
Measure the resistance of the temperature and turbidity sensor across pin 4 & 1
(10 KΩ± 1%).
200128 Fault HTR1 exceeded 176°F (80°C)
for 60 s Disconnect the power cord.
Check there is NO continuity from the tub heater element to ground.
TIP: The heater and TCO connectors have a special locking feature.
To remove, press the tab in before pulling them off the terminals.
Confirm there is continuity across the front thermal cutout.
Check that there is NO continuity from the tub heater element wire harness to
ground, including across connector PJ23.
Verify X4 is properly connected to the MCM and its contacts are clean and intact.
Check that there is NO continuity across the heating relay for X4 on the MCM.
Replace the MCM assembly.
200129 Fault HTR1 did not increase by 5°F
(3°C) during any 10 second
period during heated segment
of wash cycle.
Measure the resistance of the tub heating element (16 Ω+10% / -5% @70°F -
80°F).
TIP: The heater and TCO connectors have a special locking feature.
To remove, press the tab in before pulling them off the terminals.
Confirm the tub heater element wire harness connections are tight and continuity
of the circuit, including across both connector PJ23 and PJ33.
Verify X4 is properly connected to the MCM and its contacts are clean and intact.
Verify all insulation completely encases the tub, and none is torn, missing, wet, or
defective.
Replace the MCM assembly.
200142 Fault HTR1 did not turn off after the
door was open for 10 s Check the mechanical operation of the door latch switch.
Confirm door latch switch wire harness circuit continuity.
TIP: The continuity should change as the door latches and
unlatches.
Replace the UIM.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
Replace the MCM assembly.
200193 Fault HTR1 did not turn off after 234
minutes Disconnect the power cord.
Replace the MCM assembly.
250113 Warning
or Fault FE1 detected a leak while SOL1 is off and no active wash
cycle
Use Diagnostic Mode to flush the sump fill valve 5 times anddrain. Repeat.
Test for proper operation with a Rinse/Hold cycle.
Check the water inlet valve assembly for debris or other contaminants.
Replace the water inlet valve assembly.
250115 Warning
or Fault FE1 detected a leak while SOL1 is off and 3 recovery
SOL1 flush sequences failed
Use Diagnostic Mode to flush the sump fill valve 5 times anddrain. Repeat.
Test for proper operation with a Rinse/Hold cycle.
Use Connected Diagnostics Program to monitor fill valve state and water used.
TIP: The fill valve flowmeter should read 0 when the sump fill valve
is OFF.
Check the water inlet valve assembly for debris or other contaminants.
Replace the water inlet valve assembly.
Replace the MCM assembly.
300114 Fault Sump filtration system requires
cleaning Clean both the sumpfilterscreen and fine filter.
IMPORTANT NOTE: Use extreme caution so debris does not enter
the hydraulics. If that happens, clean and flush the hydraulics.
300137 Fault FLT1 read open (0) for 30
seconds Check for the source of the leak and repair.
Check that the base float switch is not stuck in the upward position.
Confirm the base float switch wire harness connections are tight andcontinuity of
thecircuit, including across connector PJ14.
Verify X16 is connected to the MCM and its contacts are clean and intact.
Replace the MCM assembly.
550147 Fault MCM did not receive valid
signal from AE1 for 60 s Confirm temperature and turbidity sensor wire harness connections are tight and
circuit continuity, including across pins 4 and 2 and pins 4 and 3 of connector
PJ9.
Confirm there is continuity across both pins 4 and 2 and pins 4 and 3 of the
temperature and turbidity sensor.
Verify X20 is connected to the MCM and its contacts are clean and intact.
Replace the MCM assembly.
550196 Fault AE1 unable to calibrate Clean the pylons of the temperature and turbidity sensor.
IMPORTANT NOTE: Do not misplace the O-ring.
Use Connected Diagnostics Program to monitor the continuous temperature and
turbidity value during either a Normal or Auto wash cycle.
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
TIP: Turbidity should change throughout the wash cycle as soil
enters the sump.
Replace the temperature and turbidity sensor.
560186 Fault FE1 detected insufficient water
supply to the dishwasher while
SOL1 on
Check the water supply valve to the unit. Verify there are no kinks in the water
supply line and the water supply valve is fully open.
Confirm the house water pressure is 30 - 140 psi. If not, contact the local water
utility provider.
Use diagnostic mode to test for proper operation of the sump fill valve.
Use Connected Diagnostics Program to monitor the fill valve state and water
used during the Pre-Rinse segment of a Rinse Hold wash cycle.
TIP: The fill valve flowmeter should read 937-1036 pulse counts (1.1
gal water).
Confirm the fill valve flowmeter wire harness connections are tight and continuity
of the circuit, including across connector PJ10.
Verify X19 is connected to the MCM andits contacts are clean and intact.
560187 Fault FE1 detected no water supply
to the dishwasher while SOL1
is on
Check the water supply valve to the unit. Verify there are no kinks in the water
supply line and the water supply valve is fully open.
Confirm the house water pressure is 30 - 140 psi. If not, contact the local water
utility provider.
Use diagnostic mode to activate the sump fill valve.
Use Connected Diagnostics Program to monitor the fill valve state and water
used during the Pre-Rinse segment of a Rinse Hold wash cycle.
TIP: The fill valve flowmeter should read 937-1036 pulse counts (1.1
gal water).
Confirm the fill valve flowmeter wire harness connections are tight and continuity
of the circuit, including across connector PJ10.
Verify X19 is connected to the MCM and its contacts are clean and intact.
570114 Fault Low salt in water regeneration
tank Add salt. Follow the UIM messages.
Go into the User Setup menu, and look for the Water Hardness option. If that
option does not appear, proceed to step 5.
Confirm the water softener float switch wire harness connections are tight and
continuity of the circuit, including across connector PJ10.
Verify X18 is properly connected to the MCM and its contacts are clean and
intact.
Use the Connected Diagnostics Program to verify the model type ends in "WS".
Replace the water softener tank.
570154 Fault Low rinse aid Add rinse aid. Follow the UIM messages.
Confirm the Rinse Aid Level Sensor wire harness connections are tight and
continuity of the circuit, including across connector PJ1.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
Verify X201 is connected to the UIM and its contacts are clean and intact.
580147 Fault MCM did not receive valid
signal from PE1 for 60 s Confirm sump pressure sensor wire harness connections are tight and continuity
of the circuit, including across pins 2 and 1 and pins 2 and 3 of connector PJ11.
Confirm there is continuity across both pins 2 and 1 and pins 2 and 3 of the sump
pressure sensor.
Verify X20 is connected to the MCM and its contacts are clean and intact.
Replace the MCM assembly.
600148 Fault ZE1 did not read diverter disc Insert a manual door switch activator to replicate a closed-door scenario.
Use diagnostic mode to test for proper operation of the diverter valve.
Confirm the diverter valve motor and position sensor wire harness connections
are tight and continuity of the circuit, including across connectors PJ12 and PJ27.
Verify X14 and X31 are connected to the MCM and contacts are clean and intact.
Replace the diverter valve.
Replace the MCM assembly.
600149 Fault MOT2 on for 60 s while not
calibrating Replace the diverter valve.
Verify X14 and X31 are connected to the MCM and contacts are clean and intact.
Replace the MCM assembly.
600151 Fault ZE1 read rotation of diverter
disc in 35 s Replace the diverter valve.
Verify X14 and X31 are connected to the MCM and contacts are clean and intact.
Replace the MCM assembly.
700160 Fault PE1 detected underfill condition
while no active wash cycle Check thedrainrouting from the unit. Verify there are no kinks in thedrainhose
and thedrainline high loop remains attached to the rear of the dishwasher.
Clean both the sumpfilterscreen and fine filter.
IMPORTANT NOTE: Use extreme caution so debris does not enter
the hydraulics. If that happens, clean and flush the hydraulics.
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
700165 Fault PE1 detected underfill condition
while no active wash cycle Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
700166 Fault PE1 detected overfill condition
that could not be resolved while
no active wash cycle
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
700180 Fault PE1 detected underfill condition
while no active wash cycle Check thedrainrouting from the unit. Verify there are no kinks in thedrainhose
and thedrainline high loop remains attached to the rear of the dishwasher.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
Clean both the sumpfilterscreen and fine filter.
NOTE: Use extreme caution so debris does not enter the
hydraulics. If that happens, clean and flush the hydraulics.
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
700181 Fault PE1 detected underfill condition
that could not be resolved while
no active wash cycle
Check thedrainrouting from the unit. Verify there are no kinks in thedrainhose
and thedrainline high loop remains attached to the rear of the dishwasher.
Clean both the sumpfilterscreen and fine filter.
NOTE: Use extreme caution so debris does not enter the
hydraulics. If that happens, clean and flush the hydraulics.
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
700195 Fault PE1 detected overfill condition
while no active wash cycle Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
700197 Fault Pressure sensor detected an
overfill condition that could not
be resolved while no active
wash cycle
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
800140 Fault MOT4 on for 300 s and
watchdog timer timed out Use Connected Diagnostics Program to monitordraining during a Rinse/Hold
cycle.
TIP: Drain pump motor operation should NOT occur in intervals
over 80 seconds.
Check thedrainrouting from the unit. Verify there are no kinks in the drain hose
and the drain line high loop remains attached to the rear of the dishwasher.
Clean both the sumpfilterscreen and fine filter.
NOTE: Use extreme caution so debris does not enter the
hydraulics. If that happens, clean and flush the hydraulics.
Check that the base float switch is not stuck in the upward position.
Replace the draincheck valve.
Confirm the drain pump wire harness connections are tight and continuity of the
circuit, including across connector PJ30.
Verify X7 is connected to the MCM and its contacts are clean and intact.
Confirm there is continuity across the drain pump.
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
800186 Fault MOT4 unable to calibrate
during initial drain segment of
wash cycle
Use Connected Diagnostics Program to monitordraining during a Rinse/Hold
cycle.
TIP: Drain pump motor operation should NOT occur in intervals
over 80 seconds.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
Check the drain routing from the unit. Verify there are no kinks in the drain hose
and the drain line high loop remains attached to the rear of the dishwasher.
Clean both the sumpfilterscreen and fine filter.
NOTE: Use extreme caution so debris does not enter the
hydraulics. If that happens, clean and flush the hydraulics.
Check that the base float switch is not stuck in the upward position.
Replace the drain check valve.
Confirm the drain pump wire harness connections are tight and continuity of the
circuit, including across connector PJ30.
Verify X7 is connected to the MCM and its contacts are clean and intact.
Confirm there is continuity across the drain pump.
Test for proper operation with a Rinse/Hold cycle.
Replace the pressure sensor.
900107 Fault 485 and MCM firmware
incompatible Use Connected Diagnostics Program to load the latest software for the MCM and
UIM in the following order: MCM RS485, MCM Main, UIM SW, and LCD Mem
SW.
900112 Fault UIM secondary and MCM
firmware incompatible. Use Connected Diagnostics Program to load the latest software for the MCM and
UIM in the following order: MCM RS485, MCM Main, UIM SW, and LCD Mem
SW.
900122 Fault UIM primary and MCM firmware
incompatible Use Connected Diagnostics Program to load the latest software for the MCM and
UIM in the following order: MCM RS485, MCM Main, UIM SW, and LCD Mem
SW.
900131 Fault Invalid or non-existent
development block/
configuration image within
MCM
Use Connected Diagnostics Program to load the latest software for the MCM and
UIM in the following order: MCM RS485, MCM Main, UIM SW, and LCD Mem
SW.
900132 Fault Motor control and MCM
firmware incompatible Use Connected Diagnostics Program to load the latest software for the MCM and
UIM in the following order: MCM RS485, MCM Main, UIM SW, and LCD Mem
SW.
900153 Fault UIM primary and MCM firmware
incompatible Use Connected Diagnostics Program to load the latest software for the MCM and
UIM in the following order: MCM RS485, MCM Main, UIM SW, and LCD Mem
SW.
900182 Fault No communication between
MCM and UIM Confirm the UIM wire harness connections are tight and continuity of the circuit,
including across pin 8 and 1-7 of connector PJ17 and pin 9 and 2-8 of connector
PJ11.
Verify X25 is connected to the MCM and its contacts are clean and intact.
Replace the MCM assembly.
980199 Fault Input power interruption during
active wash cycle If possible, check the quality of power delivered to the unit, including poor power
connection or damage to the power cord.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
ERROR
CODE ERROR LEVEL ERROR DESCRIPTION DIAGNOSING/TROUBLESHOOTING
Once power has been restored to the unit, verify the UIM says, "Wash cycle
interrupted. START to resume. CANCEL to exit."
Press either key, and follow the UIM instructions. The unit should either drain or
restart at the last stored safe point.
Test for proper operation with a Rinse/Hold cycle.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Listen for the change in position of the diverter valve when the wash pump
initially starts (the diverter valve rotates during this time).
If there are no leaks and the diverter valve is operating after the 15-minute
cycle completes, proceed.
Door is difficult to open or
falls open when unlatched. Door tension is out of
adjustment Set the door tension using the door tension adjustment nut.
TIP: Turn the adjustment nut clockwise to increase tension and
counterclockwise to decrease tension.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
GENERAL TROUBLESHOOTING GUIDE
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Dishwasher has no power. Power supply issue
Electrical issue
Master power switch
Control board issue
Verify the power cord is properly plugged into a power supply that meets
specifications.
Reset the power at the power supply source (electrical box or circuit breaker).
Verify the unit is on a dedicated power circuit and it does not share the circuit
with other appliances.
Verify the unit is not connected to a GFCI and, if so, that other appliances or
outlets are working.
Often, local code requires that dishwashers have an on/off switch under the
kitchen sink that supplies power to the unit. The switch may have been
accidentally turned off. Verify the switch is on and power is going to the unit.
Dishwasher does not
operate. Verify electrical power to the dishwasher and home circuit breaker is on.
Verify Child Lock mode, Sabbath mode, and Showroom mode are not active.
Unit does not start. Touch Start, and close the door within 4 seconds.
Verify Delayed Start is not turned on.
Verify the water supply is turned on.
Unit does not drain. A new installation is
not correct
The filters are blocked
The drain hose is
clogged or kinked
Debris in the drain
hose
Clogged filter
Blocked drain pump
Blocked garbage
disposal
Plugged or blocked air
gap
Pressure sensor
clogged
If the unit has just been installed, make sure the punch-out on the garbage
disposal has been knocked out if the unit is connected to the disposal.
If the unit had been draining well and no longer is, some water left in the pump
area near the drain is normal. Some standing water may be visible with the
filters in place.
Clean the dishwasher with vinegar or Lemi Shine®to remove food and grease
build-up in the drain tube, allowing for better drainage.
To drain the unit manually, enter Service mode. Press and hold the Auto key.
Clean the unit's coarse and fine filters.
Check to make sure the drain hose has no clogs, kinks, or sharp bends.
Make sure the garbage disposal is not blocked if connected to the dishwasher.
Disconnect the drain hose from the sink's water trap, or where the hose ends.
If water backs up into the sink, check the garbage disposal and trap for
blockage.
Determine if the cone-shaped part of the drain boot is cut to the maximum size
of the fitting where it attaches. If connected to a smaller diameter hose, a clog
could occur at that transition. Remember to reconnect the drain hose.
If local plumbing code requires an air gap, make sure that the air gap is not
blocked or plugged.
"Overfill Detected" appears
on the display. Verify the water supply is turned on.
Verify the drain line is not kinked.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Water pools at bottom of
dishwasher. Clogged filter
Blocked drain pump
Blocked garbage
disposal
Kink in drain hose
Plugged/blocked air
gap
Some water in the unit's drain area is normal. If the water level is above the filter
screen:
Verify the cycle was complete before the dishwasher was opened. If not, allow
it to complete and check again.
Clean the filters, and check for blockage in the drain pump.
If the dishwasher is connected to a garbage disposal and water backs up into
the sink, check the garbage disposal and trap for blockage. Disconnect the
hose leading to the disposal or air gap device, and run water through it to verify
blockage.
Check for a kink or a sharp bend in the drain hose.
Verify the drain hose is installed properly. The hose should be 20" to 35" above
the floor, and it should not drop down low before the drain hookup.
If local plumbing code requires an air gap, make sure that the air gap is not
blocked or plugged.
If water backs up into the dishwasher when using the sink, there is a blockage
in the sink's drain. Contact a plumber.
No water to dishwasher. Check for error codes.
Verify the water shut-off valve is in the open position.
Check for crimps in the water supply line.
Make sure the door was firmly closed before turning on the unit.
Verify the filters are clean.
Verify Delayed Start is not turned on.
Make sure the spray arms are not clogged with debris or hard water deposits.
Verify the water supply pressure is between 30 - 140 psi. If necessary, consult
a plumber.
Unit will not turn off. Cycle times can vary. See Dishwasher Cycle Times to verify if the unit is
operating normally. Otherwise, touch Cancel to cancel the cycle.
Reset the unit at the circuit breaker for one minute, and retest.
Unit beeps randomly. Disconnect power to the unit at the circuit breaker for 10 seconds.
Controls are unresponsive. Close the door completely, then open the door.
Verify Child Lock mode and Sabbath mode are not active.
Dishes are not dry. Verify rinse aid is being used and the compartment is full.
Add an Extended Dry or Extra Dry option to the wash cycle.
Scale and hard water
deposits appear in
dishwasher and on dishes.
Use the included test strips to check water hardness.
Softener units: Adjust the hardness setting or add salt to the whole-house
softener (if present).
Non-softener units: Add salt to the whole-house softener (if present), or
consider upgrading to a softener unit.
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828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Dishes are not clean after
wash cycle. Spray arms not
rotating or clogged
Old, too much or too
little dishwasher
detergent
Lack of rinse aid
Wrong wash cycle
selected
Dishwasher not loaded
properly
Clogged filters or drain
Diverter valve not
working
Make sure dishes are clean of large, caked-on food particles before placing
them in the dishwasher.
Verify proper dishwasher loading. Do not cover dishes with large bowls or other
containers. Do not place tall glassware in the corners of the baskets. Verify
nothing is blocking the dispenser door.
Clean the dishwasher if it has not been done recently.
Verify that water is entering the dishwasher and water to the unit is turned on.
Use only fresh, unscented, granular automatic dishwashing detergent. Organic
or ecologically friendly detergents are not recommended. Purchase smaller
boxes to avoid clumping.
Make sure the dispenser door is opening.
Verify water hardness matches detergent amount used and rinse aid setting.
Make sure the rinse aid dispenser is filled.
Heavier cycles are longer and use higher temperatures for dirtier loads. Use a
heavier cycle better suited for the load when needed. Heavy wash should be
run at least once a month. This can help to reduce the amount of soap residue
in the unit. Heavy wash is energy-efficient and uses very little water.
Verify the filters are clean and secured properly.
Remove and clean the spray arms.
To determine if the diverter valve is working, mark the current orientation of the
spray arms. Individually activate the spray arms, and determine if they move.
If dishes are dirty on the upper or lower rack only, verify the split-level wash
cycle was not in use.
If dishes are dirty on the top rack only, verify the spray arm is not blocked or
clogged.
Check the inlet hose for kinks or sharp bends.
Verify the dishwasher is level in the installation.
Unit stops during cycle. Too much detergent
Improper water level
Drain blocked
Unit not properly
plugged in
Tripped breaker
Listen closely to find out if the unit is or is not running when the door is closed.
Make sure the appliance is properly plugged into the electrical outlet. If the door
is open and the UIM display is not lit, there is no power supply.
Verify the dishwasher starts if the Start button is touched and the door is closed
within 4 seconds.
Reset the house breaker to the unit.
Clean the dishwasher filters.
Detergent is not being
dispensed. Moist detergent
Blocked dispenser
door
Put detergent in the dispenser only when the dishwasher is ready to run. When
using the Delayed Start option, make sure the dispenser is dry before putting
the detergent in.
Make sure detergent is not used for a Rinse or Rinse & Hold cycle. The
dispenser only opens during wash cycles, not rinse cycles.
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Confirm that the dispenser door is not blocked. Make sure that pot handles etc.
are not extended outside the lower basket edge.
Verify the china guard (the small tine running along the bottom of the rack from
left to right) is not bent. Check the frame of the upper rack to verify it is not
bent.
Remove and install the upper and middle racks to verify proper positioning. If
the middle rack is not installed, water flow may be insufficient for dissolving the
detergent.
Water may not be hot enough to dissolve the detergent. Place a detergent
tablet in the bottom of the dishwasher and run a cycle. If the detergent
dissolves, place a tablet in the detergent dispenser and run hot water through
the sink faucet before turning the dishwasher on, and retest.
Check the dispenser assembly for damage. If a dispenser gasket is needed, it
is not available as a separate part. Replace the entire dispenser.
Unit does not heat water. No hot water supplied
to the unit, or water
supply connected
incorrectly
Heater element failure
Temperature sensor(s)
failure
Control board/timer
failure
Incorrect mode/
temperature selection
Verify hot water is supplied to the unit. If the unit is a new installation, verify the
water supply lines are properly connected to the unit. Refer to the dishwasher
installation guide for further installation information.
Reset the unit at the circuit breaker, and run another cycle to see if the water
heats.
Check that the water inlet hose is connected to a hot water supply.
Disconnect power to the dishwasher.
Check water heater element and wire connections.
Check water temperature sensor(s).
Verify the front and rear thermal cutouts are not tripped.
Reconnect power to the washer. Place the dishwasher in Service mode, and
run diagnostics to confirm component and control board/timer operation.
Odor inside unit. Clean the interior and filters.
Water above filters. Clean the interior and filters.
Door does not close. Reposition the racks, and check for dish interference.
White film on interior. Clean the interior, and use less detergent.
Drain pump runs
continuously. When the drain pump runs all the time, and the only way to shut it off is to turn the main power switch off, verify the water is draining out. This may also sound like a
motor running constantly.
Verify the air gap is not blocked.
The drain pump is activated by the float switch. Verify no water has leaked into
the drain pan under the unit, tripping the float switch.
If there is no water in the dishwasher and the drain pump continues to run,
check the pressure switch.
Be sure that the wire connections are tight at both the pressure switch and
the connections at the timer and control board in the door.
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Remove the two wires attached to the switch, and make a connection
between the two wires.
If the drain pump stops, change the pressure switch.
If the pump continues to run and the connection is not broken at the
control board in the door, change the board or timer.
Dishwasher fills when not
in use. Leaking water valve Check if the unit is on metered fill or timed fill. A bad flow meter may incorrectly
detect water fill.
If the water level raises too high, the drain pump will automatically turn on to
drain the water.
Dishwasher is leaking. Dishwasher is not level
Bad door gasket
Crack in tub
Loose or cracked drain
hose
Verify the dishwasher is level. Tilting forward can cause water to pool at the
front of the unit, causing it to escape through the corners at the bottom of the
door. Refer to the dishwasher installation guide for further installation
information.
Check that the unit was mounted using the correct mounting screw holes. Units
installed using side trim holes may cause slow leaking due to the door not
sealing properly against the gasket.
Verify the two red spacers at the top of the tank on the left- and right-hand
sides are removed.
Verify the spray arms are rotating freely. If a spray arm gets caught pointing at
the door, water can leak from the corners at the bottom of the door.
Check the drain hose and water inlet hose. Verify the hoses are not cracked; if
so, replace them. Verify the hoses are secured tightly and not loose.
Verify the door gasket is not cracked, torn, or pulled away in any area. Replace
the door gasket as needed, or install it if it is pulled out.
Make sure the dishwasher lower air duct is attached properly to the air channel.
Inspect the tub for cracks or separation. Verify all screws are in place and
secure. If the tub is damaged, no troubleshooting is available.
Dishwasher makes
gurgling noise when
running.
Diverter valve leak Verify water leaking into the base is not causing the float switch to trip.
Verify water is not visibly leaking from the diverter valve. If so, replace the
diverter valve assembly. When installing the new diverter valve assembly, use
soapy water on the O-rings and avoid folding or rolling them.
After installation, test the diverter valve:
Run a RINSE & HOLD cycle, found in CYCLES+.
Check that there are no leaks from any connection on the diverter valve,
wash pump, or sump.
Listen for the change in position of the diverter valve when the wash pump
initially starts (the diverter valve rotates during this time).
If there are no leaks and the diverter valve is operating after the 15-minute
cycle completes, proceed.
Issue with air
accumulator Replace the sump assembly (which contains the air accumulator).
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Dishwasher makes noise
during drying. Drier fan is hitting a
machining chip (small
white plastic circles)
Run the Normal cycle. If the noise is present during the drying phase:
Remove the kickplate from the unit.
Use a flashlight to inspect the drier duct for any obstruction.
Remove the obstruction.
If there is no obstruction, replace the drier fan.
Door cannot close fully. Door latch is sprung in
the wrong position If the door latch is sprung in the wrong position, it can be reset in one of two ways:
Use a hook to reset the latch to the correct position.
If the door panel is removed, place a small tool into the 1/4" hole in the upper
door brace. Press on the latch, and it will snap back into the correct position.
Water leaking from the
front of the tub. Unit is not level Adjust the front by turning the front leveling legs clockwise to raise and
counterclockwise to lower the unit.
Adjust the rear by turning the rear adjustment screw counterclockwise to raise
and clockwise to lower the unit.
TIP: The unit is equipped to prevent the rear leveling leg from
stripping if turned the wrong way. If the rear leveling leg does not
raise or lower, tilt the dishwasher forward slightly to remove pressure
from the leg, which will engage the threads and allow adjustment.
Fill level appears too high
or too low. Possible feature of
typical operation The fill level is not constant between modes, and it is not constant between cycle
segments. However, the most typical fill volume for any wash segment is 1 gallon.
Problems with water supply
to spray arms. Diverter valve not
functioning Connect the unit to water.
Connect the unit to power.
Run a RINSE & HOLD cycle, found in CYCLES+.
Check that there are no leaks from any connection on the diverter valve, wash
pump, or sump.
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
828019 REV B 08/2023
DW2450 and DW2450WS Service Manual
service.subzero.com 800.222.7820
Error Codes and Troubleshooting
PROBLEM POSSIBLE CAUSES SOLUTION/ACTION
Listen for the change in position of the diverter valve when the wash pump
initially starts (the diverter valve rotates during this time).
If there are no leaks and the diverter valve is operating after the 15-minute
cycle completes, proceed.
Door is difficult to open or
falls open when unlatched. Door tension is out of
adjustment Set the door tension using the door tension adjustment nut.
TIP: Turn the adjustment nut clockwise to increase tension and
counterclockwise to decrease tension.
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