APRILIA ATLANTIC 125 Workshop Manual page 210

ELECTRICAL SYSTEM
Coolant thermistor test
•
Remove the thermistor (1),
•
Set a multimeter (2) to the Ohm range and attach the
multimeter leads to the thermistor (3) as shown in the
figure.
•
Suspend the thermistor (1) in a container (3) filled with
coolant.
•
Suspend a thermometer (4) with a 0 -150°C (32 -
302°F) range in the container.
•
Place the container on a gas burner (5) and heat up
the coolant gradually.
•
Check the temperature reading of the thermometer (4)
and the thermistor (1) output indicated by the
multimeter.
Thermistor output should vary with temperature as indicated
in the table below.
Coolant temperature
100 (°C) 212 (°F)
80 (°C) 176 (°F)
60 (°C) 140 (°F)
40 (°C) 104 (°F)
NOTE Change the thermistor (1) when meter reading does
not vary with temperature, or when the readings found
deviate too much from the values indicated in the table.
FUEL LEVEL
Dashboard indicator test
•
Disconnect the sensor connector and connect a
resistor across the yellow-green and blue wires at the
connector end.
•
Set the key to ON and note the dashboard indicator
reading.
Ratings of resistors to be connected to the connector
- Resistor rated 10 ohm  : full tank indication
- Resistor rated 38 ohm   : half scale +-5°
- Resistor rated 90 ohm  : empty tank and light on
Fuel sensor test
•
Disconnect the sensor connector,
•
Connect an ohmmeter to the yellow-green and blue
wire terminals. Measure resistance output at different
fuel levels.
- Correct reading with a full tank: less than 10 ohm
- Correct reading with 8 litres of fuel: 38 ohm ± 10%
- Correct reading with empty tank: greater than 90 ohm
8 - 16
5.4.1.
Correct reading
(Ω)
144
262
512
1090
4.1.3.
ATLANTIC 125 - 200