Testing Control Board; Testing The Capacitors - Viking RDSCE2305B Service Manual

Troubleshooting
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.
To check the individual direction and speeds,
perform the following checks:

Testing Control Board

Leave the Molex connector attached to P4
board connection. While the convection fan
is turning in the forward direction (clockwise),
use a voltmeter to measure voltage between
the blue/black wire in the Molex plug and
the red wire (L2) at the line break relay. The
voltage should be 240 VAC. This will indicate
the K5 and K6 of the oven control board are
functioning properly.
Leave the Molex connector attached to P4
board connection. While the convection
fan is turning in the reverse direction
(counterclockwise), use a voltmeter to
measure voltage between the orange/black
wire in the Molex plug and the red wire (L2)
at the line break relay. The voltage should
be 240 VAC. This will indicate the K5 and
K6 of the oven control board are functioning
properly.
18
! WARNING
When K7 is at rest, testing between LO and
L2 should show a voltage reading of 240
VAC. The red LED in front of the relay will
NOT be lit. When K7 is energized, testing
between HI and L2 should show a voltage
reading of 240 VAC and the red LED in front
of the relay will be illuminated.
If voltage is not present, this indicates a faulty
relay and the oven control board will need to
be replaced. Also check wiring to the main
power supply and repair/ replace as needed.

Testing The Capacitors

The range uses two 2 F capacitors. Using
either an analog or digital meter, use your
highest ohms setting and check between
each terminal of the capacitor. Make sure
one of the leads to the capacitor is temporally
removed. On an analog meter, the pointer
will increase until it reaches its capacitance
(nearly infinity), then return to 0 ohms.
Reversing the leads will repeat the process.
On a digital multimeter, the pointer is replaced
by the value displayed by a numerical number
in the display. It too will return to 0 ohms
indicating a good capacitor.
If the capacitor(s) is open, then it will never
charge. If it is shorted, the resistance will
be infinite immediately and won't change. If
either is true, replace the capacitor(s).
©2012 Viking Preferred Service