Mitsubishi Lancer Evolution IX. Manual - part 648

INDIVIDUAL COMPONENT SERVICE

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-105

INDIVIDUAL COMPONENT SERVICE

M1524002900431

WARNING

•

If heat damage may occur during paint work, remove the SRS-ECU, the driver’s and pas-
senger’s (front) air bag modules, the clock spring, front impact sensors and the seat belt 
with pre-tensioner. 

•

SRS-ECU, driver’s and passenger’s (front) air bag modules, clock spring and front 
impact sensors: 93

°

 C or more

•

Seat belt with pre-tensioner: 90

°

C or more

•

If the SRS components are removed for the purpose of check, sheet metal repair, painting, 
etc., they should be stored in a clean, dry place until they are reinstalled.

If the SRS components are to be removed or replaced as a result of maintenance, troubleshooting etc., follow 
the service procedures that follow. (Front impact sensor; refer to 

P.52B-107

, SRS-ECU; refer to 

P.52B-109

, 

Driver’s and passenger’s (front) air bag modules and clock spring; refer to 

P.52B-110

, Seat belt with pre-ten-

sioner; refer to 

P.52B-117

).

WARNING/CAUTION LABELS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-106

WARNING/CAUTION LABELS

M1524003000431

Caution labels on the SRS are attached in the vehicle as shown. Follow label instructions when servicing the 
SRS. If the label(s) are dirty or damaged, replace with new one(s).

AC504533 AC

HOOD

Seat belt with pre-tensioner
(driver's and passenger's seat)

Clock spring

Passenger's (front)
air bag module

Instrument panel

Front impact sensor

Steering wheel

SRS-ECU

Sun visor

NOTE 
  : Indicates RHD vehicles. For LHD vehicles, the specified application position of label is reversed left to right.

 

FRONT IMPACT SENSORS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-107

FRONT IMPACT SENSORS

REMOVAL AND INSTALLATION

M1524001500407

WARNING

•

Disconnect the negative battery terminal and wait for 60 seconds or more before starting 
work. Furthermore, the disconnected battery terminal should be covered with tape to 
insulate it.

•

Never attempt to disassemble or repair the front impact sensor. If faulty, replace it.

•

Do not drop or subject the front impact sensor to impact or vibration. If denting, cracking, 
deformation, or rust are discovered in the front impact sensor, replace it with a new front 
impact sensor. Discard the old one.

•

After deployment of an air bag, replace the front impact sensor with a new one.

NOTE: The figure on the left indicates the left front 
impact sensor.

Pre-removal Operation

• Turn the ignition switch to the "LOCK" (OFF) 

position. 

• Disconnect the Negative Battery Terminal.

AC311090

1

Radiator

5.0 ± 1.0 N·m

AB

Removal step 

1.

Front impact sensor
Installation steps 

>>

A

<<

•

Pre-installation inspection

>>

B

<<

1.

Front impact sensor

•

Negative battery cable connection

>>

C

<<

•

Post-installation inspection

FRONT IMPACT SENSORS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-108

INSTALLATION SERVICE POINTS
>>A<<PRE-INSTALLATION INSPECTION

When the new front impact sensor refer to the previ-
ous item "INSPECTION."

>>B<<FRONT IMPACT SENSOR 
INSTALLATION

WARNING

The SRS may not activate properly if a front 
impact sensor is not installed properly.

1. Securely connect the connector.
2. Position the front impact sensor facing toward the 

front of the vehicle as shown by the arrow on the 
label, and install it securely.

>>C<<POST-INSTALLATION INSPECTION

1. Connect the negative battery cable.
2. Turn the ignition switch to "ON" position.

3. Does the SRS warning lamp illuminate for about 7 

seconds and then goes out?

4. If no, refer to troubleshooting (Refer to

P.52B-9

).

INSPECTION

M1524001600374

WARNING

If a dent, crack, deformation or rust is 
detected, replace with a new sensor. 

1. Check the front impact sensor for dents, cracks, 

deformation or rust. 

WARNING

Always replace the sensor with a new one if 
the resistance shows a short or open circuit.

2. Check short or open circuit between the terminals 

of the front impact sensor.

Short circuit: 2 

Ω or less

Open circuit: 2 M

Ω or more

3. Check the continuity between the terminal and 

bracket. If there is a continuity, the insulation is 
malfunctioned, and replace the sensor with a new 
one.

4. Check the head lamp support pane for 

deformation and rust.

AC311044

SRS warning lamp

AB

ACX00597AC

ACX00598 AC