Specifications

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Data Parameters Engine Parameters
Turbo systems rely on the ECU to vary current to the EGR switchover valve, which regulates
vacuum to the EGR valve. The greater the control current, the greater the EGR flow.
ELECTRIC AIR PUMP
Range: __________________________________________________________ ON/OFF
Used on ME27 and ME28 systems. This parameter indicates the state of the electric air pump,
on or off. The air is forced into the exhaust manifold through the air pump switchover valve.
These air injection systems only operate during cold and warm-up conditions.
ELECTRIC COOLING FAN
Range: __________________________________________________________ ON/OFF
Used on HFM and ME20 systems. This parameter indicates the state of the electric cooling fan.
The ECU switches the fan ON when engine coolant temperature reaches a certain point.
ENGINE BRAKE TORQUE
Range: __________________________________________________________ variable
Used on HFM systems. This parameter is an ECU-calculated value that indicates engine torque
as newton-meters (Nm). Engine load partially determines engine brake torque.
ENGINE COOLANT TEMPERATURE(V)
Range: ________________________________________________________ 0 to 5.00 V
ENGINE COOLANT TEMPERATURE(°)
Range: _________________________________________–40 to 255°C or –40 to 491 °F
Used on ARA/ELR, DM, DM2, EDS, ERE/EVE/ASF (IFI Diesel)), EZ, HFM, ME10, ME20, ME27,
and ME28 systems. This parameter displays either the voltage drop created by the resistance of
the engine coolant temperature (ECT) sensor, or the calculated temperature based on the
voltage signal. The ECT is a negative temperature coefficient (NTC) sensor, so resistance
decreases in proportion to temperature increases. The display should read high voltage on a
cold startup, then gradually drop as the engine warms up. In most cases the engine coolant
temperature will be displayed in °C. The measurement units can be changed from degrees
Celsius (°C) to degrees Fahrenheit (°F).
ENGINE LOAD
Range: _________________________________________________________ 0 to 100%
Used on ME10, ME20, ME27, ME28, and SIM4 systems. This parameter is an ECU-calculated
engine load displayed as a percentage. The ECU determines engine load based on RPM,
number of cylinders, airflow, and cylinder air charge. Input sensor readings are compared to a
theoretical air charge that occurs at standard ECU temperature and pressure (volumetric
efficiency). The resulting ratio, called engine load, is expressed as a percentage. With the engine
running at idle under a normal load readings should be between 20 to 40%. During normal
driving, load should be lower than 80%.
The ME-MOTRONIC engine management system uses torque-led control, which means it
calculates the internal torque produced during combustion. This is the physical force produced
by gas pressure during the compression and power strokes. The actual net torque of the engine
has to account for friction, gas transfer losses and drive power for ancillary equipment, such as
the water pump, alternator and AC compressor. The ME program contains the optimal
specifications for charge density, injection duration, and ignition timing for any desired torque,
which makes it possible to obtain optimal emissions and fuel consumption for every operational
mode. Operational demands are prioritized and coordinated individually to use the appropriate
control to achieve the specified torque. Torque based control is possible because the electronic
accelerator permits throttle valve control beyond the pedal value inputs.