PIAGGIO 500 cc Service Manual page 202

Fuel injection
To control the stepper and related circuit, proceed as follows.
Connect the diagnosis tester 020460Y. See page 9-17.
Set ignition to "ON" with switch in position "RUN" and side stand raised.
Lift the vehicle with the central stand.
Select the "errors " function from the menu
Check if the control unit has registered anomalies
concerning the stepper circuit.
YES
NO
Select the "parameters" function from the menu
Check the number of "steps" programmed by
the control unit to achieve ignition.
This arrangement is a function of the engine
temperature.
20° C = ~ 80-90 steps
YES
Start the engine and allow it to warm up.
With a coolant temperature greater than 70°C,
the control unit should command the stepper
with around 20 "steps".
NO
YES
NO
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