Gilera 633721 Workshop Manual page 217

Nexus 500 euro 3
10 - Line to earth. In this case, the pump always starts to rotate if there is a continuous power supply.
YES point 12
11 - Interrupted line. The relay cannot control the pump feeding
YES go to 13
12 - Check and restore the earth insulation of the control unit line 19 and of the pump remote control
switch line 85.
YES go to 14
13 - Install the special tool between control unit and the injection system.
YES go to 15
Specific tooling
020481Y Control unit interface wiring
14 - Delete the code and check from the beginning.
15 - Set the switch to "ON" with switch to "RUN"
and side stand raised. Wait more than two sec-
onds and check the following conditions:
19 - 23 = battery voltage
YES go to 16 NO go to 17
16 - Replace the control unit.
17 - Check the presence of voltage (+ batt.) be-
tween pin 86 of the pump remote control switch
and pin 23 of the control unit. Fix the wiring, if re-
quired. Check the relay coil continuity.
85 - 86 = 100 ± 50Ω
18 - Check that fuse 12 is in working order
YES go to 20 NO go to 19
Injection
INJEC - 217