Thermostatic Switch; Temperature Sensor - Honda NX250 1989 Manuals

THERMOSTATIC SWITCH

The cooling fan motor is actuated by the thermostatic switch
located in the bottom of the radiator.
If the fan motor does not start, disconnect the 2P: Black con-
nector from the switch.
Connect together Black/Blue and Green terminals of the 2P
connector with a suitable jumper wire.
Turn the ignition switch ON. The cooling fan motor should
start running. If it does not start, check for battery voltage
from the Black/Blue lead of the fan motor connector and
ground with ignition switch ON.
If there is no voltage, check for a blown fuse, loose terminals
or connectors, or an open circuit.
If there is voltage, inspect the thermostatic switch as follows:
Drain the coolant (page 5-4) and remove the thermostatic
switch.
Connect one lead of an ohmmeter to the connector of the
thermostatic switch and the other to the body.
Suspend the thermostatic switch in a pan of coolant (50 — 50
mixture) and check the temperatures at which the switch
opens and closes.
Make sure that there is no continuity at room temperature and
then gradually raise the coolant temperature. The switch
should show continuity (close) at 93°—97°C (199° —
207°F}.
NOTE
• Keep the temperature for 3 minutes to confirm continuity.
A sudden change of temperature will Cause an incorrect
temperature reading between the thermometer and switch.
• Do not let the switch or thermometer touch the pan as it will
give a false reading.
• Immerse the switch in coolant up to its threads.
Install the thermostatic switch.
TORQUE: 18 N*m (1.8 kg-m, 13ft-lb)
Fill the cooling system (page 5-4),

TEMPERATURE SENSOR

Disconnect the Green/Blue wire from the temperature sensor.
Check for continuity between the sensor body and ground.
There should be continuity.
If there is no continuity, check the thermostat housing for
looseness and recheck.
•
LIGHTS/METERS/SWITCHES
( 1 | THERMOSTATIC
(2) THERMOSTATIC
SWITCH
(1 TEMPERATURE SENSOR
SWITCH
(1) THERMOMETER
19-9