APRILIA SL 750 SHIVER Service Station Manual page 226

Power supply
Throttle Body The two throttle bodies are made up of:
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Throttle valve with 2 return springs for the controlled minimum opening position.
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DC electrical motor
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Tinned double throttle position sensors with magnetic control (contactless)
The throttle bodies do not require any maintenance and cannot be overhauled. In case of electric or
mechanic malfunction, replace the whole unit.
Pressure sensors The pressure sensors (one per cylinder) are fundamental not only for the injection
map at low and stabilised speeds but also for checking the Ride by Wire system: their signal is connected
to a TORQUE CHAIN for checking the correct opening of the throttle valves.
Intake air temperature sensor The signal coming from the sensor is used to calculate the estimated
torque since the oxygen in the air also depends on its density which varies according to temperature.
2 - Injection/ignition control
Map for injection type (alpha-D)/rpm where:
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alpha is the throttle position
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D is the pressure measured at inlet ducts
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Rpm are the engine revolutions
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At idle and for slow and stabilised speeds D/n
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For medium-high throttle openings alpha/n
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For temporary speed (speed change) alpha/n
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The main parameters that correct the injection map are:
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Engine temperature
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Atmospheric pressure (calculated)
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Lambda probe signal
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Air temperature
3 - System safety checks
The checks are structured in several levels:
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Level 1 - sensor correct operation
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Level 2 - comparison between requested torque and estimated torque generated by the
engine
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Level 3 - a microprocessor controls the correct operation of the regular microprocessor
The consequent maintenance operations may be of different gravity according to the level and the
defective component:
A the malfunction does not affect riding in safety, the warning light turns on, the word Service is dis-
played, the signal recovery value considered not reliable is used and the engine works regularly.
B the malfunction may affect riding in safety, the warning light turns on, the message Urgent Service is
displayed, the torque demands are not fully activated (reduced torque).
C the malfunction may affect riding in safety, the warning light turns on, the message Urgent Service
is displayed, the engine operates in Limp Home function (accelerated idle), the throttles which are at
P SUPP - 4
SL 750 SHIVER