To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING
!
Testing Fan Motor
If all the voltage tests on the oven control
board are correct, the capacitors and the
convection motor need to be checked.
With the Molex connector removed from
the P4 board connection and capacitor
leads removed, use an ohmeter to measure
resistance between blue/ black wire (forward
direction) in the Molex plug and the red
wire at the line break relay. The resistance
should be approximately 100 ohms. Likewise,
the reverse direction can be measured by
reading resistance between the yellow/white
wire in the Molex plug and the red wire at
the line break relay. Resistance should be
approximately 100 ohms. If either or both
readings are not as shown, replace the
convection fan motor (Follow the convection
fan disassembly procedure).
Door Lock Assembly
The door lock motor is a 240 VAC motor. One
side of the motor is wired directly to L2 (red
wire). L1 power to the lock motor is connected
on the P12 connector (DL) on the main
control board. When the relay energizes, L1
power is sent to the lock motor. The photo
below shows the P12 connector.
There are three microswitches mounted on
the door lock assembly. One switch is not
used on this model.
When the door is in the unlocked position,
the cam is depressing the S1 switch
plunger. The N.O. switch contact is closed
and a completed circuit is made at the P15
connection between the brown and blue/
white wires. This signals the board that the
door is unlocked.
S2 is also N.O. and is open when the door is
unlocked. When the lock motor is activated
and begins to lock, the S1 contact opens.
When the plunger catches the door liner
and pulls inwards, the S2 switch plunger
is actuated. The switch contact is closed
and a completed circuit is made at the P15
connection between the brown and orange
wires. This signals the board that the door is
locked.
When it is time to unlock the door, power is
sent to the door lock motor and it continues
its rotation. The plunger releases the door
liner and opens the contact on S2. When
the door is fully opened, S1 is closed by the
motor cam. This will signal the board that the
door is unlocked.
Troubleshooting
©2012 Viking Preferred Service
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