CHECKING CONTINUITY
To make component or wiring measurements, set an ohmmeter’s RANGE switch at R x 1 (unless directed
otherwise.) For all “ground” measurements, set the RANGE switch to R x 10k. Insert the ohmmeter
probes into the plug pins or against the component terminals as directed in the procedure.
COMPONENT TEST PROCEDURE METER READINGS
THERMISTOR The thermistor can be tested by
Temperature (*F) = Resistance(Ohms)
measuring the resistance between
The GY wires at the thermistor con- 35*F = 8240 - 8926 65*F = 3628 - 3930
nector or at the DC connector of the 40*F = 7143 - 7739 70*F = 3189 - 3455
electronic control board. Making the 45*F = 6209 - 6727 75*F = 2810 - 3044
test at the board is an easy way to 50*F = 5410 - 5860 80*F = 2480 - 2687
check out the thermistor wiring har- 55*F = 4724 - 5118 85*F = 2194 - 2376
ness. The “Meter Readings” show 60*F = 4235 - 4479 90*F = 1945 - 2107
the thermistor resistance over a
range of temperatures.
DEFROST Disconnect the defrost heaters wire The ohmmeter should indicate approxi-
HEATER connector from the wiring harness. mately 19 ohms to 20 ohms.
Touch the ohmmeter probes to the
Connector pins.
Ground Test: Touch one probe to Should indicate an “open’ circuit for both
the chassis and the other to each pins. Any resistance indicates a short
connector pin. circuit.
BIMETAL Make sure that the freezer is cold
Enough to close the bimetal con-
tacts. The bimetal contacts close
At approximately 20*F +/- 8*F and
open at approximately 50*F +/- 8*F.
Disconnect the 2-pin bimetal con- Continuity if the evaporator temperature
nector (PX and BR wires) from the is below 12*F. No continuity if the
wiring harness. Touch the ohmmeter evaporator temperature is above 56*F.
Probes to the pins on the ends to the
Wires.
EVAPORATOR Disconnect the wire terminals from The ohmmeter should indicate between
FAN MOTOR the motor. Touch the ohmmeter 40 ohms and 80 ohms.
probes to the motor terminals.
Ground Test: Touch one probe to Should indicate an “open” circuit.
the chassis and the other to each Any resistance indicates a short circuit
wiring connector.
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