Iveco Daily Euro 4. Manual

Steering angle sensor

102116

It measures the steering angle required by the driver.

The comparison between this signal and those from all the other sensors allows the ESP control unit to define the actions to be
taken. The hydraulic unit controls brake pressure as quickly as possible, separately for every single wheel.

Moreover, the ESP system may decrease the engine revs number by means of the engine control feature.

Steering angle sensor calibration

112243

With both the steering-wheel and the wheels in straight position (after checking toe-in), you will obtain the sensor “zero” condition
through the diagnosis instrument, i.e. you will assign its absolute zero position.

Use a diagnosis instrument to clear the errors.
Carry out a road test, to make the control unit verify whether errors are still found. Drive along a straight road at a speed of
approximately 50 k.p.h. Steer to the right and then to the left several times, after making sure you do not endanger other drivers.

You need not oversteer to cause the ESP warning light to come on.

NOTE

Drive back to the service centre, then use a diagnosis instrument to verify that the anomaly is no longer found.

Figure 124

Figure 125

102110

128

ELECTRIC/ELECTRONIC SYSTEM

AILY

URO

ESP control unit programming

112243

Entering the variant codes: type of drive, engine, MTT, wheelbase, type of front and rear suspensions, height.

Easy compares the type of vehicle (PIC reading) with the control unit code, to avoid installation errors (single wheels instead
of dual), and downloads the variant codes into the control unit.

Clear the errors (if any) by means of the diagnosis instrument.

Carry out a road test. Drive along a straight road at a speed of approximately 50 k.p.h. Brake suddenly as if in an emergency,
after making sure you do not endanger other drivers: you should feel the system “respond” on the brake pedal. This test makes
the control unit verify whether errors are still found.

Drive back to the service centre, then use a diagnosis instrument to verify that the anomaly is no longer found.

Replacing ESP central unit needs the longitudinal acceleration sensor calibration that was already described in previous page.

The steering angle sensor, in this case, is not to be calibrated as it has its own internal memory.

Figure 126

102109

ELECTRIC/ELECTRONIC SYSTEM

129

AILY

URO

130

ELECTRIC/ELECTRONIC SYSTEM

AILY

URO

General

The air bag is a passive safety device comprising one or two cushions which, in the event of a head-on crash, inflate automatically
setting themselves between the body of the occupants and the front structures of the cab.

The system is always integrated by seat belts with pretensioner, which are controlled by the air bag control unit, in the event
of head-on crashes.

The system does not cut in for front crashes at low speed, side crash, overturning or crashes from behind.

Inflation of the bags without the restraint of the belts compromises the safety of the driver and passengers.

System components are connected to each other and to the rest of electrical system through a special wiring harness that can
be easily identified as it is provided with a yellow sheathe.

SYSTEM OPERATION

Device intervention sequence can be INDICATIVELY REPRESENTED as illustrated in following figure.

For convenience’s sake, drive side device only is shown: passenger side air bag operation is quite similar.

Represented diagrams are qualitative and are not concerning subject vehicle.

Diagram A: this diagram represents inflation pressure in cushion versus crash dynamics developing time.

Diagram B: this diagram represents body positions during a front crash with respect to steering wheel and air bag positions.
Below is events time sequence from the time of electrical pulse triggering off by electronic central unit.

Time “t1”

Time when inflation system is triggered off. Thereafter, inflation pressure starts rising in the cushion, which is still enclosed inside
module cover. The module is made up of a plastic layer located at steering wheel centre. Driver’s body is still in almost normal
position (Figure B, reference 1).

Time “t2”

Pressure inside still closed module rises until it reaches such a value that the cover is opened, cushion stuck out and inflation
started.
Driver’s body starts in this time period to move forwards and is placed between normal position taken during drive and the
position of the collision against the cushion (Figure B, reference 2).
At the time when the cushion is released from its shell, gas pressure slows rapidly down owing to the high inertia of the cushion.
At a certain time, pressure is drawn to take negative values.

Time “t3”

Cushion pressure takes back positive values because from this time the very inflation starts which will lead the cushion to
maximum expansion condition.

Time “t4”

Driver’s body impact against the cushion takes place (Figure B, reference 3).
Pressure inside the cushion rises because of pressure exerted on it by driver.

Time “t5”

Pressure in the cushion slows rapidly down owing to the presence of an air vent hole and the cushion deflates entirely to the
end of allowing driver high mobility (compatible with the rest of the vehicle).

The air bag is complementary to the use of the seat belts and not in replacement of them.

NOTE

ELECTRIC/ELECTRONIC SYSTEM

131

AILY

URO

Figure 127

Content .. 259 260 261 262 ..

Iveco Daily Euro 4. Manual - part 261