Chery A15 / 480 LHD model. Manual - part 34

safety memory unit before handling with the steering system. In order to
remove or install the airbag components, please disconnect the negative grid
of the battery and wait for at least 1 minute.

Removal/Installation

The hairspring is installed between the steering wheel and the steering column. When
installing the hairspring, pay attention to the installing position and direction, otherwise it
would cause insufficient turning angle or heavy rotation of the steering wheel.

In order to remove and install the hairspring, it is necessary to check the hairspring clearance
during rotating.

Warning: In order to check the clearance, turn the hairspring carefully until we can feel the
resistance. After that turn back for about 4 cycles and align it with the clearance marking.

Scheme of the hairspring installation

4. AIRBAG COMPONENTS

(1) Airbag components

The  airbag  components  consist  of  the  airbag  decoration  cover,  airbag  and  inflating
components. The airbag is made of nylon fabric. The internal layer was treated with synthetic
glue  for  sealing  air.  When  the  airbag  is  not  open,  it  is  folded  like  a  bag  of  the  unopened
parachute and installed between the upper part of air inflator and the airbag cover. There is a
impression line for tearing on the surface of the airbag decoration cover so that the decoration
cover can  be torn off easily during the  inflation of the airbag and reduce  its resistance to let
the airbag passes through.

When  the  vehicle  is  collided,  normally  the  airbag  will  start to  inflate  within  10ms  after  the
first  collision,  and  the  total  inflation  time  from  the  starting  of  inflation  through the  entirely
activation of the airbag is about 30mS. When the airbag is activated, it spreads out along the
steering  column  to  the  direction  of  the  windshield  and  thus  prevents  the  driver’s  face  to
collide with the windshield, and his chest to collide with the steering wheel.

There is an air discharging hole at the back of airbag (opposite to the driver). When the driver

Fastening

mark

Turning mark

presses on the airbag due to the effect of inertia, the airbag is pressed and the air will be
discharged from the discharging hole, so that the kinetic energy resulted by the collision
between the driver and the airbag can be absorbed, which preventing the driver from injuring.

The  function  of  the  inflator  components  is  such  that  when  the  igniter  activates  the  ignition
agent,  generating  air  and  inflating  the  airbag,  causing  the  airbag  to  spread  out.  When  the
computer sends the ignition instruction, the heating element circuit turns on, which is heated
quickly  and  activates  the  ignition  agent,  the  activated  ignition  agent  explodes  immediately
and generates heat, and then the inflating agent is heated up and decomposed to generate the
air into the airbag.

(2) BCM (airbag control module)

Irreparable component. It is the component of the monitoring system during operation and
sends the instructions when the airbag function.

Record any detected malfunction.

Turn on the warning lamp to warn the driver that there is a malfunction.

Diagnose malfunction code can only be detected by the diagnostic tester.

The BCM controls the inflation and spreading of the airbag through the following

preheat

fastening ring assembly

machine base
2 bolts
tightening torque

inflation assembly

lid

components:

·Safety sensor

·Capacitor

·Collision sensor or accelerometer

(4) Capacitor

The capacitor provides the backup power.

(5) Bulb

When the operation voltage is increased to the BCM point, the BCM will trigger the warning
lamp and we can now check the bulb. The BCM turns on the warning lamp for 4 seconds and
then turn it off during the bulb inspection.

Malfunction Display

The airbag control module records the malfunctions of the system in two forms.

1. Current malfunction.

2. Historic malfunction detected before.

(6) Warning lamp

·When any malfunction appears, the malfunction warning lamp will be turned on.

·It is kept “on”.

(7) Wiring harness

Most of the wiring harness linkers adopted in the airbag system are yellow.

FAULT DIAGOSIS, INSPECTION AND OPERATION

1. INSPECTION OF SRS DIAGNOSIS SYSTEM

When the supplementary restriction system (SRS) is turned on, the airbag controlling module
(BCM)  will  turn  on  the  airbag  warning  lamp  and  start  system  self-diagnosis.  The  warning
lamp  will  flash  for  6  seconds  with  frequency  of  1Hz  during  the  system  diagnosis.  If  BCM
diagnoses  any  malfunction,  it  will  turn  on  the  airbag  warning  lamp  and  record  the
malfunction  into  the  BCM  memory.  The  BCM  will  diagnose  the  SRS  system  malfunction
automatically once it is turned on.

If 5 consecutive malfunctions are diagnosed during the self-checking, the SDM will mark the
malfunction.  A  malfunction  diagnosis  test  cycle  is  400  milliseconds,  so  that  the  SDM  will
confirm the malfunction within 2 seconds (400 milliseconds x 5 times). If the malfunction is
marked and maintained as the malfunction state, the warning lamp will be “ON” continuously.
This  state  is  called  the  “existing  malfunction”.  Once  the  malfunction  is  marked,  and  if  this
malfunction  does  not  appear  again  after  25  continuous  fault  diagnosis  test  cycles  (400

milliseconds X25=10 second), the malfunction mark will be cancelled. The warning lamp
will be turned off under this condition, and it is called the “historical malfunction”.

2. DIAGNOSIS OF THE DIAGOSTIC TESTER

The diagnostic tester can read data from the BCM memorizer to carry on the continuous data
exchanging. The diagnostic tester is used for reading and storing the malfunction codes, and
clears part of the stored data after the maintenance. But it can not clear the interior
malfunctions, such as the accident records and the arithmetic data malfunctions.

The proper usage of the diagnostic tester: firstly, turn off the ignition switch, connect the
diagnostic tester to the OBDII connector, and then turn on the ignition switch. See the
diagnostic tester manual for the follow-up procedure.

SRS SYSTEM MAINTENANCE AND OPERATION

If it is required to inspect the vehicle protection supplementary system or inspect the accident
vehicle, the procedures below should be followed. If any malfunction is found, the
corresponding parts should be replaced by new ones.

1. MAINTENANCE OF SRS SYSTEM

Warning: When the ignition is turned off and at the same time the fuse is taken out, the sensor
and the diagnostic module (BCM) can provide the sufficient voltage for 1 minute to activate
the airbag. If the airbag is not disconnected, then do not start the maintenance work within 1
minute after turning off the power supply to BCM. If the airbag has been disconnected, then
the maintenance work can be carried out immediately without waiting for the 1 minute
electrical discharging time. The failure of shutting off the SRS system temporarily during the
maintenance will result in false ignition, physical injury and SRS system discarded.

(1) Turn off the airbag system

Adjust the steering wheel to the center position, turn the ignition switch to “Lock” position
and remove the key, remove the airbag fuse from the fuse box and wait for more than 1
minute for BCM capacitor discharging.

(2) Turn on the airbag system

Insert the airbag fuse into fuse box, turn the ignition switch to “ON” position, and inspect
whether the airbag indicator lamp is off after being on for 6 seconds. If the indicator lamp
does not function in this way, please refer to the “Diagnosis and inspection of SRS system” of
this manual.

Warning: When the ignition switch is turned on, keep away from the airbag as far as possible,
otherwise it may cause physical injury.

(3) Operation, installation and diagnosis

The airbag should be placed in an environment with the temperature not higher than
65℃(149℉). If the airbag drop from a height of more than 0.9 meter (3 feet), the airbag and

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