KitchenAid KBFC42FS, Техническое образование

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5-1
COMPONENT TESTING
Electrical Shock Hazard
Disconnect power before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical shock.
WARNING
Refer to page 4-5 for the procedure for ac-
cessing the thermistor.
1. Unplug refrigerator or disconnect power.
2. Disconnect the thermistor connector from
the wiring harness.
3. Set the ohmmeter to the R x 10 scale.
4. Touch the ohmmeter test leads to the
connector pins. The meter should indi-
cate as shown in the chart.
NOTE: If the resistance of the thermistor is
normal, perform the following voltage test.
5. Set the voltmeter to read a maximum
voltage of 10 volts DC.
6. Connect power to the refrigerator and al-
low it to enter the “cooling” mode.
THERMISTOR
Before testing any of the components, per-
form the following checks:
Control failure can be the result of corro-
sion on connectors. Therefore, disconnect-
ing and reconnecting wires will be neces-
sary throughout test procedures.
All tests/checks should be made with a
VOM or DVM having a sensitivity of 20,000
ohms-per-volt DC, or greater. •
•
Check all connections before replacing
components, looking for broken or loose
wires, failed terminals, or wires not pressed
into connectors far enough.
Resistance checks must be made with pow-
er cord unplugged from outlet, and with wir-
ing harness or connectors disconnected.
Unless stated otherwise, make all resis-
tance checks by disconnecting the compo-
nent connector at the Central Control Unit
(CCU). •
•
•
TEMP RESISTANCE TEMP RESISTANCE
(
°
F)
Ω
(APPROX.) (
°
F)
Ω
(APPROX.)
–5 25900-27500 45 5930-6300
0 22100-23500 50 5190-5510
5 18900-20000 55 4550-4830
10 16200-17200 60 4000-4240
15 13900-14800 65 3520-3730
20 12000-12800 70 3100-3300
25 10400-11000 75 2740-2910
30 8990-9550 80 2430-2580
32 8750 85 2160-2290
35 7800-8290 90 1920-2030
40 6800-7220
7. With the thermistor disconnected and the
refrigerator in the cooling mode, touch
the voltmeter test leads to the thermistor
main harness connector pins. The me-
ter should indicate approximately 5 volts
DC.
If the voltage is not present, check for
a thermistor output at the main control
board (see page 5-8).