PIAGGIO 500 cc, Service Manual

Page: 181 / 239

Fuel injection
9 - 69
9
The coil circuit control is
efficient.
Install the connection harness between the control unit and fuel injection
Special tool 020481Y (see page 9-8)
Proceed with secondary
control of the della HV coil,
cable and shield cover
(see page 9-68 and 9-72)
Measure the tension between pins 20 and 23 of the
special tool during the fuel pump timing phase.
To activate timing set to "ON" with switch on "RUN"
and side stand raised.
20-23 = Battery tension (matched with pump
revolution - 2 sec.)
If an increased time available for the test is desired,
activate the "relay pump diagnosis" function
(30 seconds)
The coil primary control circuit is efficient.
Check the connections with the control unit
and coil accurately.
If necessary proceed with replacement of the control unit.
Disconnect the connection with the HV coil primary
Repeat the tension control between the black-green
wire and the earth.
Black-green-23 = battery tension
(matched with pump revolution -2 seconds)
Check continuity of the black-green wire.
Repair or replace the harness.
NOTE : any anomaly of the command electromagnetic switch would
lead to failed pump turning. (see page 9-53)
NO
YES
NO
YES
YES
NO