PIAGGIO 633823 Service Station Manual page 232

Suspensions
1: RIDER PRESENCE SENSOR
With interface wiring disconnected from the control
unit and connected to the system, check the fol-
lowing conditions:
pin 17 - 36: resistance 15 ÷ 18 kOhm when the
rider is not seated on the saddle.
pin 17 - 36: resistance of about 3 kOhm when the
rider is seated on the saddle
SUSP - 34
MP3 250 i.e.