Iveco Daily Euro 4. Manual - part 265

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It is a part which is installed on steering column switch unit and used to enable the connection cables of the cushion on steering
wheel to follow steering wheel rotation without risks of breakage.
The device is made up of two caps: lower cap is fixed to steering column switch unit by three screws, while upper cap is made
integer to steering wheel through two add-ons inserted on upper side.
Inside the two caps, connection cables are wound up in a spiral shape in order that they are enabled to follow movements.
Spiral contact is also equipped with a device which automatically locks spiral contact rotation when spiral contact is removed
from steering wheel; this is done in order to prevent upper cap, that is not constrained any more, from freely rotating, so causing
the cables to unexpectedly unwind or wind up and creating consequent risks of cable breakage.
On steering wheel mounting operation, the device is automatically locked.

- Where spiral contact is disconnected/reconnected, it must be made sure that it is remounted on the steering

column switch unit in the same position it was removed.

- Where spiral contact is replaced, if it is provided as a spare apart from steering column switch unit, then spiral

contact must be installed with wheels perfectly aligned, because this is new device corresponding position.

Figure 133

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Pyrotechnic device that can be electrically activated by a signal from central unit, it is an integrating part of safety belts rolling up
device, so that a single component is created which is fixed to vehicle pillar.

In the case of a crash having a certain extent, it intervenes in such a way that it recovers the unavoidable stretch of the belts caused
by the action exerted by body weight and it keeps the body adherent to seat back.
At the end of intervention, the belt remains locked, so highlighting that device intervention has occurred.

Operation principle

At the time when a determined deceleration of the vehicle occurs, the electronic sensor, that is placed in control central unit,
sends a signal which ignites gas generator pyrotechnic charge (detonator).
Propellant combustion develops a gas the pressure of which generates a force pushing rack piston upwards.
Rack piston upward movement rotates gear wheels, which reverse tape rotation direction, so winding back the tape by a few
centimetres.

After every crash, the belt becomes unusable: therefore, it must be replaced.

The charge for driver side pretensioner is connected to central unit on pins A9/A10.

The charge for passenger side pretensioner is connected to central unit on pins A11/A12.

The charge for central pretensioner is connected to central unit on pins B17/B18.

Figure 134

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On door pillars, two air bags named “curtain” air bags are provided. These devices intervene in case of a side crash. For this
purpose, two (lh & rh) sensors are present which detect the occurrence of this event.
For the connections of these components, see central unit pin-out and relating electrical scheme.

Figure 135

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A. “Curtain” air bag - B. Side crash sensor

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Figure 136

Figure 137

ISOLATING THE BATTERY CABLES

REMOVING THE CENTRAL UNIT

COMPONENT REPLACEMENT
INTERVENTIONS

Electronic central unit

To remove the central unit, the following is needed:

- observing safety rules;

- disconnecting battery cables (first negative cable, then

positive cable) and isolating them by applying an adhesive
tape on pins (Figure 136);

- waiting for at least ten minutes before resuming

operations;

- removing the protection under which central unit is

located;

- operating using a small screwdriver on connector stops

locking connector fastening levers and rotating the levers
inwards;

- disconnecting the connectors from central unit;

- unscrewing the three screws which fasten central unit to

floor (Figure 137).

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