PIAGGIO 500 cc Service Manual page 183

YES
Check continuity of the HV coil primary
See diagram
Resistance of the primary = 0,5Ω ± 8%
YES
Check the earthing isolation of the primary circuit
Measure between one of the two terminals of the
primary and the earth.
Primary-earth = Ω infinity (>1MΩ)
NO
Disconnect the connector between the vehicle system and the
fuel injection system.
Repeat control of the earthing isolation in the two sections.
Repair or replace the harness concerned.
Repeat control using "active diagnosis" from the menu for HV
coil command simulation.
Cancel the errors present in memory.
YES
Fuel injection
NO
9
NO
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