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19
NX6 / NX8 / NXA Models
Refrigerator Service Manual
NORCOLD
A
MODE
COLD
COLDEST
COLD indicator light(s) will flash OFF/ON at 1-second intervals (Only while control is “Awake”)
A
NOR000122-10A
A
fl
ashing COLD temperature indicator (snow
fl
ake) means
the electronic controls have sensed the
fi
n thermistor to be
inoperable. This fault is only displayed while the optical display
is awake. To wake the optical display, press and release either
the Mode or Temp Set buttons. If a problem is sensed with
the thermistor the COLD temperature indicator (snow
fl
ake)
will
fl
ash ON and OFF. After 10-seconds the control will revert
back to the sleep mode. This fault can be displayed in ANY
MODE. Should the thermistor be sensed inoperable the
electronic controls will ignore the thermistor and revert to a
BOS mode (Backup Operating System). Refer to Backup
Operating System (BOS) Mode section of this manual-on
"Backup Operating System (BOS) Mode" on page 14.
Verify:
• The lamp-thermistor wire assembly is plugged in and
that the connections are not dirty or broken (see Fig.
5A).
• Thermistor resistance (see Fig. 5B).
Fig. 5A - Thermistor
Fig. 5B - Thermistor in Ice
Thermistor Fault
Door Fault
There is no displayed fault for an open door however; the
interior light will automatically be turned off in the event the
door has been sensed open for more than 2-minutes. The light
switch, a magnetically activated reed switch attached to the
optical display board, is activated by a magnet located beneath
the refrigerator doors top trim piece. When the magnet is
close to the reed switch (door closed) the light remains off;
when the magnet is away from the reed switch (door open) the
light is turned on. The open/closed status of the reed switch
On-Off Theory of Operation:
Continuous 12-Volts:
See Fig. 6.- page 21
12VDC is supplied to the refrigerator at Power Board terminals
12VDC & GND [A]. This 12VDC travels through the Power
Board to fuse F1 [B] and then out to P1-6 [C]. Via the green
wire, the 12VDC exits the Power Board and enters the Display
Board at P1-1 [D]. The 12VDC travels through the Display
Board to one side of the normally open On-Off switch [E]. This
12VDC is referred to as the continuous 12-volts because it
is always present at the one side of the On-Off switch when
12VDC power is applied to the refrigerator.
Switched 12-Volts:
See Fig. 7. - page 21
Pressing the On-Off switch [E] will allow 12VDC to pass
through the On-Off switch and back to the Power Board via
the blue wire [F] connected between the Display Board at P1-3
and the Power Board at P2-3. Once the 12VDC reaches the
Power Board, a signal is sent out to the coil of relay K3 [G]
via the U1 microprocessor. This signal allows the K3 relay to
energize thus closing the normally open contacts [H].
Blank Display
is monitored by the optical display board and communicated
back to the power board which in turn activates the interior
light output accordingly. Because the switch operates via the
proximity of the magnet, it is important that the door alignment
is correct. To test for interior light operation, refer to Interior
Light Test on "Interior Light Test Procedure" on page 25.
NX61 / NX81 Fault Codes - cont’d
