© 2010 Viking Preferred Service
34
Service Diagnostics and Procedures
Control Board Diagnosis
Convection Relay
When the convection element is selected, voltage
is sent to the convection relay coils. A red LED
(D26) in front of each coil verifies coil voltage is
being sent to that particular relay. This means
that 12 VDC is being sent to the relay coil. It does
not indicate that the relay contacts are closing.
When the convection element relay is energized,
power (L1-black) is sent through the relay to the
convection element. Power (L2-red) is supplied by
the line break relay).
To test, select a cooking program. When the
convection relay contact is energized (D26 at
base of relay illuminates red), check for 240 VAC
between the yellow wire at the line break relay and
the white/red wire on P2. If 0 VAC is measured,
disconnect power
and remove P2
Molex plug.
Reconnect power
and using an Ohm
meter, check for
continuity between
the two relay
contacts. When the
relay is energized;
if infinite ohms (Ω)
are measured this indicates a bad relay and you will
need to replace the control board. If 0 ohms are
measured, the relay contact is closing.
Cooling Fan
Locate the P11 connector on the control board.
The P11 connector will have a Molex plug
containing white/black wires.
With the Molex connector removed from the P11
board connection, use an Ohm meter to measure
resistance between one of the white/black wires
and neutral at P1 on the power supply board.
The resistance should be approximately 18 Ω. If
no resistance is measured, remove fan to repair
or replace as necessary (see Oven Cooling Fan
Disassembly, page 56).
With the Molex connector attached to the P11
board connection, use a voltmeter to measure
voltage between the white/black wire of the Molex
plug and the white wire in the Molex plug at the P1
power supply board. The voltage should be
120 VAC. If 120 VAC is present and no fan rotation,
replace the cooling fan (see Oven Cooling Fan
Disassembly, page 56). If no voltage is present,
verify wiring. If wiring is OK, check the relay on the
control board.
P-11
P-11
LED
Place meter
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