L322 Range Rover System Description and Operation
ENGINE MANAGEMENT SYSTEM – V8
18-2-16 DESCRIPTION AND OPERATION
System Inputs
The ECM optimises engine performance by interpreting signals from numerous vehicle sensors and other inputs.
Some of these signals are produced by the actions of the driver, some are supplied by sensors located on and around
the engine and some are supplied by other vehicle systems. The inputs are as follows:
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Ignition switch
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Accelerator pedal position sensor (APP)
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Throttle position feedback
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Crankshaft Position (CKP) sensor
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Cruise control signal (from steering wheel switch pack)
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Brake light switch
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Camshaft Position (CMP) sensors
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Engine Coolant Temperature (ECT) sensor
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Knock sensors
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Air Mass/Intake Air Temperature (MAF/IAT) sensor
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Heated Oxygen Sensors (HO2S)
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Immobilisation signal (from immobilisation ECU)
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Fuel level signal (via CAN)
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Vehicle speed signal (from ABS ECU)
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Radiator outlet temperature sensor
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Internal ambient barometric pressure sensor (altitude sensor)
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Electronic Automatic Transmission (EAT) information.
Electric Throttle System
The EMS incorporates an electric throttle control system. This system comprises three main components:
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Electronic throttle control valve
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Accelerator pedal position sensor (APP)
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ECM.
When the accelerator pedal is depressed the APP sensor provides a change in the monitored signals. The ECM
compares this against an electronic “map” and moves the electronic throttle valve via a pulse width modulated control
signal which is in proportion to the APP angle signal.
The system is required to:
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Regulate the calculated intake air load based on the accelerator pedal sensor input signals and programmed
mapping
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Monitor the drivers input request for cruise control operation
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Automatically position the electronic throttle for accurate cruise control
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Perform all dynamic stability control throttle control interventions
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Monitor and carry out maximum engine and road speed cut out.
