Rotax 915 i A series Maintenance Manual page 414

SYSTEM DESCRIPTION
GENERAL NOTE
In order to ensure that the engine is in the desired
operating state and in full working order, a number of
sensors are placed on it and used for the Engine
Management System (EMS). The information cap-
tured by the sensors is transmitted to the ECU where
it is processed, and the corresponding signals are
sent on to the actuators.
SENSORS
1 Pressure/temperature sensor – ambient
pressure
Wiring harness designation: AAPTS
Ambient air pressure and ambient temperature are
measured with a combined pressure/temperature
sensor. These measurement values are used to
compensate for the different altitude and external
temperatures.
1 Pressure sensor – oil pressure
Wiring harness designation: OPS
The pressure sensor measures the oil pressure of
the engine.
2 Pressure sensors – airbox
Wiring harness designation: MAPS_1/MAPS_2
The pressure sensors measure the pressure of the
intake air in the airbox.
2 Temperature sensors – airbox
Wiring harness designation: MATS_1/MATS_2
The temperature sensors measure the temperature
of the intake air in the airbox.
4 Temperature sensors – exhaust
Wiring harness designation: EGT_1/EGT_2/ EGT_3/
EGT_4
The temperature sensors measure the temperature
of the exhaust gas and are used to regulate the injec-
tion quantity.
1 Temperature sensor – cooling system
Wiring harness designation: CTS
The temperature sensor measures the coolant tem-
perature directly in the cylinder head of cylinder 4.
1 Temperature sensor – oil temperature
Wiring harness designation: OTS
The temperature sensor measures the oil
temperature.
76–70–00
Page 6
August 01 2018
BRP-Rotax
MAINTENANCE MANUAL HEAVY
1 Knock sensor
Wiring harness designation: KNOCK
"Knocking" means uncontrolled combustion in petrol
engines, which is caused by auto-ignition of the mix-
ture in the combustion chamber. This undesirable
combustion results in increased mechanical loads in
the engine.
Operation in this condition over a long period can
damage or even destroy the piston. Characteristic
frequencies are generated during knocking. These
frequencies are detected by the knock sensor and
sent to the control unit (ECU).
1 Potentiometer – throttle valve
Wiring harness designation: TPS
The potentiometer measures the position of the throt-
tle valve in the throttle body.
4 Double ignition coils
Wiring harness designation: COIL_1/COIL_2/ COIL_
3/COIL_4
Each double ignition coil supplies 2 spark plugs with
high voltage.
2 Crankshaft position sensors
Wiring harness designation: CPS_1/CPS_2
The control unit (ECU) requires the current position
of the crankshaft for exact control of the ignition and
injection points. The crankshaft position sensors
measure the revolutions of the crankshaft and give
the ECU information about the position of the pistons
and the position of the crankshaft.
ACTUATORS AND INDICATORS
Injectors (INJ_1 to INJ_8):
In the engine, eight injection valves (INJ) are used,
two for each cylinder.
Ignition coil (IGN): (Ignition Coil)
Four double ignition coils (with one primary coil and
one secondary coil each) are attached to the engine.
Each end of the secondary coil is connected to a
spark plug of different cylinders by ignition cables.
Pressure control valve (PCV)
Electromechanical control device, used to control the
gas flow in the area of turbocharger, pop-off valve
and wastegate.
Effectivity: 915 i A Series
Edition 0/Rev. 0