Fiat 1998 Marea Weekend, Service Manual

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Marea- Marea Weekend
1999 range
Electrical equipment
Air Bag - New features
55.
SYSTEM WITH SIDE BAG
The side impact protection system, or side bag, fitted as an option on the car, extends the system already
present on the car and offers maximum protection to front seat passengers by protecting critical body ar-
eas.
The side bag system is controlled integrally with the two front air bags by a control unit that reads and
processes deceleration and impact data from two sensors located in the car's side pillars.
The system consists of:
- control unit (50 pin)
- side bag modules within the front seat squabs, on the side facing the outside of the car;
- side deceleration sensors.
CONTROL UNIT FOR AIR BAG. SIDE BAG AND PASSENGER PRESENCE SENSOR (PPD)
SYSTEM
The control unit for the system with side bag differs from the unit used with the system made up of driver
air bag, passenger air bag, pretensioners and passenger presence sensor because it is able to process data
sent by satellite side sensors and features a different pin out: the control unit is connected to the system
via a 50-pin connection.
The system with side bags operates in the same way as the system with front air bags.The control unit is
calibrated in accordance with specific activation thresholds that ensure the unit operates only in the case
of impacts where the occupant requires additional protection. It is able to differentiate between these im-
pacts and other events where operation is not necessary (low-energy side impact, blows against the side
not caused by other vehicles, etc.).
The control unit is programmed to deactivate the front air bag, the side bag module on the passenger side
and the associated pretensioner if the presence sensor detects the continual absence of a passenger for at
least 30 seconds, and to reactivate them immediately as soon as a passenger presence is detected.
In the case of an air bag system with side bag, the wiring branch is monitored continuously by the control
unit while the car is in use. If an anomaly is detected, the red failure warning light is activated and the
system operates in conventional manner to keep the driver and passenger side air bags operational at all
times.
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