MOTO GUZZI NEVADA 750, Service Station Manual

Page: 44 / 128

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If the circuit is open, shorted to positive: check sensor connector and Marelli control unit
connector; if not OK, restore cable harness; if OK, check sensor continuity; if it is not OK,
replace the sensor; if it is OK, check continuity between PIN 4 of the control unit connector
and the PIN marked by the orange cable of the sensor: restore cable harness if there is not
continuity; if it is OK, reconnect the control unit connector and, with key set to ON, check
continuity between the PIN marked by the grey cable of the sensor connector and the vehicle
ground connection: if there is not continuity, restore cable harness; if there is continuity, it
means that the error cause is a shorted-to-positive cable; therefore, restore cable harness
between PIN 4 of the control unit and the PIN marked by the orange cable of the sensor. If
the engine air temperature sensor error is displayed at the same time, it means that there
is a short circuit to positive in the grey cable of both sensors.
•
If shorted to negative, check sensor correct resistance: if resistance = 0, replace the sensor;
if resistance is correct, it means that the cable has ground connection: restore the cable
harness.
Air temperature sensor
Function
It tells the control unit the intake air temperature in
order to calculate oxygen presence so as to opti-
mise the petrol quantity necessary for correct com-
bustion.
Operation / Operating principle
NTC type sensor (resistance sensor, inversely
variable with temperature).
Level in electrical circuit diagram: Temperature
sensors
Location:
•
sensor: on the right side of the filter
box, next to the control unit
•
connector: on the sensor
Electrical characteristics:
•
Resistance at 0°: 9.75 k
Ω
± 5%
•
Resistance at 10°: 5.970 k
Ω
± 5%
•
Resistance at 20°: 3.747 k
Ω
± 5%
•
Resistance at 25°: 3.000 k
Ω
± 5%
•
Resistance at 30°: 2.417 k
Ω
± 5%
Pin-out:
Electrical system
NEVADA 750
ELE SYS - 44