PIAGGIO 500 cc Service Manual page 191

The air intake temperature sensor is inserted in the lower part of the throttle body from the filter box side.
The sensor is an NTC and has the same function layout as the coolant temperature sensor.
This signal is used to optimize the engine functioning. It is, however, a less influential signal than that of the coolant
temperature.
In case of circuit damage, the control unit commands the lighting up of the fuel injection indicator and activates
protection control, thus guaranteeing engine function.
To control the sensor and related circuit, proceed as follows.
Connect the diagnosis tester 020460Y.
See page 9-17.
Select the "ERRORS" function from the menu.
Check if any anomalies concerning the air intake
temperature sensor have been registered.
NO
The EMS system has not received temperature indications not included in
If it is suspected that a temperature indication is incorrect, proceed with
controls as indicated below.
Before proceeding with control of the sensor and related circuit, it is advisable to wait until the engine has
cooled completely so that the vehicle is adjusted to the working ambient temperature.
Set ignition to "ON" with switch on "RUN" and side stand raised.
The three indications are equal or differ by little (for example, 1°C)
YES
The air intake temperature sensor is probably
the field of those possible.
On the diagnosis tester, select the "parameters" menu
Do not start the engine.
Check indications for:
coolant temperature
air intake temperature
ambient temperature indicated by the digital instrument.
giving a correct indication.
Install the special tool 020481Y. See page 9-8.
Do not connect the control unit connector
Fuel injection
YES
9
NO
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