APRILIA RSV4 ABS 2009 Manual page 398

Power supply
a variable geometry control unit for managing the
system, interfaced with the engine injection control
unit
Operation
At key-ON, the variable geometry control unit low-
ers the ducts (if still in the raised position).
Subsequently, depending on the control voltage
on PIN 2 from the injection ECU (0V down, 5V up),
the ECU drives the electric motor with the relative
polarity for raising or lowering the ducts.
The drive voltage delivered to the motor is deter-
mined in relation to battery voltage and the motor
is stopped once a given current limit is reached or
if the time-out period of 500 ms has elapsed.
There is no feedback relative to duct position! If in
doubt, use the diagnostic instrument to actuate the
ducts.
In the case of a defect in the variable geometry
control unit, an error message is sent immediately
to the engine injection ECU.
The variable geometry control unit does store er-
rors
See also
P SUPP - 398
RSV4 ABS