AIRBAG - Functional description

Functional description

The Air Bag system control unit M60 receives a supply controlled by the ignition (INT) at pin 2 of connector A from the line protected by fuse F50 of the junction unit under the dashboard B2.

Pin 1 of connector A is connected to the special earth C50.

Early crash sensor K39 detects slight bumps and reports them to control unit M60 - pin 12 of connector A of M60.

When a frontal impact of a certain severity (depending on the control strategy, data from the above two sensors and sensors incorporated in the control unit) is detected, the control unit sends control signals for stage 1 operation of the front modules:

• to driver's Air Bag Q9, via the steering wheel clockspring D47 (from pins 15 and 16 of connector A of M60):
• to the passenger airbag Q11 (from pins 13 and 14 of connector A of M60);
• to the pretensioners on the driver's side Q20 (from pins 23 and 24 of connector B of M60) and the passenger side Q21 (from pins 21 and 22 of connector B of M60);

When frontal impact of a certain severity is detected, the control unit sends control signals to set off the stage 2 front modules:

• to driver's Air Bag Q9, via the steering wheel clockspring D47 (from pins 19 and 20 of connector A of M60 ):
• to passenger side air bag Q11 (from pins 17 and 18 of connector A of M60 ):

A signal from passenger Air Bag disabling switch H75 reaches pin 9 of connector A of M60.

The side impact detection sensors K66 (driver's side) and K67 (passenger side) send signals to pins 2 and 1 respectively of connector B of the control unit M60.

When side impact of a certain severity (dependent on the software setting) is detected, the control unit sends control signals to set off the modules:

• to driver's side front Air Bag Q30 (from pins 19 and 20 of connector B of M60);
• to passenger side front Air Bag Q31 (from pins 17 and 18 of connector B of M60);
• to the driver's Head Bag Q40 (from pins 15 and 16 of connector B of M60);
• to the passenger Head Bag Q41 (from pins 13 and 14 of connector B of M60).

The seat structure that houses the side bags is connected to earth C50.

The driver's seat belt switch I45 is connected to the control unit sending an earth signal to pin 10 of connector B of M60.

The control unit M60 is connected, via the CAN line, to the Body Computer M1 and to the instrument panel E50.

When the system self-diagnostic function detects a fault or an impact is detected, control unit M60 sends a signal, via the CAN, to the Air Bag failure warning light located in instrument panel E50 similarly for the passenger Air Bag disabled warning light and the seat belts not fastened warning light.

Self-diagnostic data can be read by connecting to connector C of Body Computer M1: it receives data from the control unit M50 via the CAN.