Chery A15. Manual - part 123

 

 OPERATION CONDITIONS 

----The airbag system will function under the 

following conditions: 

1) When the vehicle is collided with a 

stationary object with a speed over 
25Km/H, the airbag will be activated. 

2) When two vehicles have a head-on 

collision both with a speed over 25Km/H, 
the airbags of the two vehicles will be 
activated. 

3) When one vehicle is parked, and anther 

vehicle is collided with it face to face with 
a speed over 50Km/H, the airbags of the 
two vehicles will be activated. 

4) Collision within the included angles of 30

o 

from the left and right of the vehicle. 

----The purpose of SRS is to protect the driver 

during a serious head-on collision. If the 
external force is coming from the included 
angle within 30 degree of the vehicle 
centerline, the airbag will be activated.   

----Note: The above vehicle speed is referring 

to the speed measured by the sensor, not 
the actual speed of the vehicle. The speed 
measured inspected by the sensor is 
related with the actual speed, bumper 
performance results and the crossbeam 
deformation. 

 
 

 
 

OPERATION PROCESS 

----The activation process of the airbag. 

 

 

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----- -The accident happens; 

Sensing; 

Triggering; 

The airbag is activated and inflated; 

 

 

 

 

----The airbag inflates completely; 

The driver moves forward; 

 

----The driver’s head and upper body bump 

into the airbag; 

The air is discharged through the rear end 
of the airbag. 

 

----The air is totally discharged from the 

safety airbag. 

The operation process is as follows: 

The electronic accelerometer can 
continuously measure the acceleration and 
deceleration of the vehicle and then 
transmit the signals to microprocessor. 

The perfect collision signals process in the 
microprocessor determines whether and 
when to activate the airbag. 

If it is necessary to activate the airbag, the 

 

Serious breakage delay 

Exceeding malfunction signal

Accident sensor

 

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microprocessor will activate the ignition 
circuit. 

If the electric safety sensor is turned off at 
the same time, the ignition current will 
induce the igniter, and activate the safety 
airbag. 

 
 
THE ASSEMBLY PARTS OF AIRBAG AND WORKING PRINCIPLE 

SRS (airbag system) includes: 

Steering wheel airbag components; 

Airbag control module; 

Steering column hairspring; 

Wiring harness; 

SRS malfunction warning lamp. 

 

1. COLLISION SENSOR (IN THE BCM) 

The collision sensor or the accelerometer employs an electronic instrument to display the 
acceleration or deceleration of the vehicle during the head-on collision. In the display of 
electronic instrument, the electronic signals equally reflect the acceleration or deceleration of 
the vehicle. (Acceleration of gravity) 

The computer will determine the severity degree of the collision according to the strengths of 
electronic signals. If the electronic signals exceed the pre-set value, the airbag computer will 
send the ignition demand to the igniter to activate the ignition agent, and heat and decompose 
the inflating agent to generate the required air for inflation of the airbag. 

 

2. SAFETY SENSOR (IN THE BCM) 

Most of the vehicles employ a short circuit plate structure for the linkage of the airbag 
computer and the igniter to prevent the false ignition of airbag. The safety sensor installed in 
this vehicle is a kind of safety device consists of a dual contactor and an electric switch. 

It acts independently with the electronic components. During normal driving, the ignition 
circuit of airbag maintains at the “standby”. This will ignite the airbag under the required 
conditions. (More than 6.4 acceleration of gravity)   

 

 

 

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3. HAIRSPRING 

In order to ensure that the steering wheel has a 
sufficient turning angle other than damages 
the connection wiring harness of the airbag 
assembly, the spiral wiring harness is adopted 
between the steering wheel and the steering 
column. Install the wiring harness into the 
spiral spring first, and then install the spiral 
spring into the spring housing, which is called 
as hairspring. Normally, the wiring harness of 
the horn is also installed in the spiral spring. 

 

Specification: 

External diameter：Φ96m 

Number of cycles: maximum cycles of 6. 

Storage temperature : -40～85 

Operation temperature: -35℃～85℃   

Operation voltage: DC 9～16V 

Working current (airbag configuration): 16A，40V－6ms max. 

Current carry capacity: Carrying up to 5S maximum under a load current of 5A 

Voltage carry capacity: Carrying up to 100ms maximum under a voltage of DC 20V 

Operation torque: 0.15ms max. 

Hairspring 

It is installed on the steering column. 

It is also a part of the horn circuit. 

Attention: The hairspring will be damaged if the steering wheel is turned by more than 

4.5 cycles. 

Turn the steering wheel: 

Rotate the steering wheel to one direction will tighten the coil. 

Rotate the steering wheel to the other direction will loosen the coil. 

The hairspring will be damaged if the steering wheel is turned by more than 4.5 cycles.(The 
total rotation range: 9 cycles) 

Warning: Removal of the hairspring will cause injury and vehicle damage. Do not 

remove the hairspring. If the airbag has already been inflated, the hairspring 
must be replaced. Please remove the airbag components, hairspring and 

 

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