Drain Motor; Moisture Sensor; Diverter; Water Temperature Sensor - Viking VDB200 Service Manual

Service Diagnostics and Procedures
Control Board Diagnosis

Drain Motor

The dishwasher uses a drain motor to remove water
from the tub at timed intervals during the wash
cycle. In the drain mode, voltage between P6-4 and
neutral should be 120 VAC. If voltage is measured,
unplug the wires to the drain motor and using an
ohmmeter, check for approximately 15.1
at the valve. If 0 ohms are read, replace the drain
Ω
pump. If readings are correct, remove pump and
check for obstructions in the drain pump (see Drain
Motor Disassembly procedure, page 30).
P-6
P-10
Note: Testing the drain motor can be achieved in
the diagnostic mode.

Moisture Sensor

The dishwasher uses a moisture sensor that is
mounted in the base pan of the dishwasher. Any
moisture that comes in contact with the sensor
will cause the unit to stop filling, operate the drain
pump, and signal an error code. If the sensor is
open, an open fail code will signal (see Fail Codes,
page 13). Resistance between P8-1 and P8-2 should
be 175K ohms.
Ω
P-8
© 2010 Viking Preferred Service
(Some measurements require power and others require the unit not to be powered.)
ohms
Ω
P-6
P-10
P-8
Wash Diverter
The dishwasher uses a wash diverter to divert water
to either the upper arm or lower arm during the
wash cycle. This allows for low water consumption
and a better wash to both upper and lower racks.
At the beginning of each wash cycle, the control
board positions the wash diverter to its proper
starting position. It is monitored by a built in
monitoring switch that sends 120 VAC back to
P6-5. Depending on how long the switch is closed
determines what position it is in.
To check the wash diverter, check the motor with
an ohmmeter between P6-2 and Neutral. It should
read approximately 2.7k
incorrect, verify wiring connections to the diverter.
If the wiring is proper, replace the wash diverter
(see Wash Diverter Disassembly procedure,
page 30).
Note: If the diverter does not position itself, a
Diverter time out error will display (see Fail Codes,
page 13).
P-6
P-10
ohms. If readings are
Ω
P-6
P-10
17