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Function of sensors, driver area
Clutch pedal position breaker
Controlled mechanically by the clutch pedal. When the
clutch pedal is depressed, this position breaker disen-
gages the cruise control.
Sensors on engine
Intercooler air temp. sensor 7067
The intercooler air temperature uses the control unit in
order to reduce fuel flow with abnormally high inter-
cooling air temperature.
Charge pressure sensor 7066
It is the charge pressure that determines the fuel flow to
the engine at a particular speed.
756B
753B
Coolant temperature sensor 756B
The coolant temperature uses the control unit to deter-
mine the following: start fuel flow, fuel flow at full
load (should the coolant temperature exceed a fixed
value), low idle speed with cold engine, speed limita-
tion during a certain period after starting.
Extra speed sensor 753B
In addition to the charge pressure, it is important that
the control unit knows the engine speed, otherwise it
cannot determine the fuel flow. The function of the
EDC requires at least one speed signal. For this reason
the speed signals are doubled.
A speed signal is despatched as information to the con-
trol unit from the speedometer/tachograph.
Cruise control
Used for three different functions:
•
Idle speed, setting.
•
Raised idle speed (so-called “constant speed
hold”).
•
Cruise control.
The EDC-system has a diagnostic function that indi-
cates a fault via the diagnostic lamp.
Accelerator pedal position sensor
Provides information about accelerator pedal position
(and kick-down for buses with automatic transmis-
sion).
Brake pedal breaker
Disengages the cruise control with braking. Applies
also to activated exhaust brake.
