2007 MITSUBISHI LANCER EVOLUTION Service Repair Manual

SRS -Troubleshooting52B-37
Replace the SRS-ECU.
clock spring>
Measure at the SRS-ECU connector C-21.
DDisconnect the SRS-ECU connector C-21.
DDisconnect the the clock spring connector
C-204.
DIgnition switch:ON
DMeasure at the harness side
DVoltage between terminal 11 or 12 and body
earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to avoid
a possible decrease in the contact pressure.
OK:0V
NG
From Previous Page
YES (when No.62 is output)YES (when No.61 is output)
Replace the SRS-
ECU.
Correct
Check connector:C-21, C-204
Check the trouble symptoms.
Check the harness between the
clock spring and the SRS-ECU, and
repair if necessary.OK
clock spring>
Measure at the SRS-ECU connector C-21.
DDisconnect the SRS-ECU connector C-21.
DDisconnect the clock spring connector C-204 .
DMeasure at the harness side
DContinuity between terminal 11 or 12 and body
earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to avoid
a possible decrease in the contact pressure.
OK:No continuity
NG
OK
NG
OK
NG
Connector C-21 Connector C-21

SRS -Troubleshooting52B-38
Code No.64 Front passenger’s air bag module (squib)
system (short-circuited to power supply)Possible Cause
Code No.65 Front passenger’s air bag module (squib)
system (short-circuited to earth)
This code is output when the input terminal of the SRS-ECU front passenger’s
air bag module (squib) is short-circuited to power supply (code No.64) or
short-circuited to earth (code No.65).DHarness or connector fault
DThe harness of the front passenger’s air bag
module (squib) is short-circuited to power supply
(code No.64) or short-circuited to earth (code
No.65).
DSRS-ECU inoperable
the front passenger’s air bag module>
Measure at the SRS-ECU connector C-21.
DDisconnect the SRS-ECU connector C-21.
DDisconnect the front passenger’s air bag
module connector C-109 .
DMeasure at the harness side
DContinuity between terminal 9 or 10 and body
earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to
avoid a possible decrease in the contact
pressure.
OK:No continuity
NO
Replace the front passenger’s seat air bag module (squib).

MUT-II self-diag code
DConnect the dummy resistor (MB991865) to the resistor harness
(MB991866).
DDisconnect the front passenger’s air bag module connector C-109
and insert the resistor harness (MB991866) behind the harness side
connector.
Caution
Do not directly insert a probe or other devices at the front of the
connector to avoid a possible decrease in the contact pressure.
DConnect the negative ( - ) terminal of the battery
DCheck the diagnosis code again after erasing the memory.
Is code No.64 or No.65 output?
YES (when No.65 is output)YES (when No.64 is output)
Replace the SRS-ECU.
the front passenger’s air bag module>
Measure at the SRS-ECU connector C-21.
DDisconnect the SRS-ECU connector C-21.
DDisconnect the front passenger’s air bag
module connector C-109 .
DIgnition switch:ON
DMeasure at the harness side
DVoltage between terminal 9 or 10 and body
earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to
avoid a possible decrease in the contact
pressure.
OK:0V
NG
Replace the SRS-ECU.
Correct
Check connector:C-21, C-109
Check the trouble symptoms.
Check the harness between the front
passenger’s air bag module and the
SRS-ECU, and repair if necessary.OK
NG
OK
NG
OK
NG
Resistor harness
(MB991866) Dummy resistor
(MB991865)
resistance (3Ω)
Instrumental panel
wiring harness
Front passenger’s air bag
module connector
Connector C-21Connector C-21

SRS -Troubleshooting52B-39
Code No.66 Driver’s seat belt pre-tensioner (squib)
system (short-circuited to power supply)Possible Cause
Code No.67 Driver’s seat belt pre-tensioner (squib)
system (short-circuited to earth)
This code is output when the input terminal of the SRS-ECU driver’s seat belt
pre-tensioner (squib) is short-circuited to power supply (code No.66) or
short-circuited to earth (code No.67).DHarness or connector fault
DThe harness of the driver’s seat belt pre-tensioner
(squib) is short-circuited to power supply (code
No.66) or short-circuited to earth (code No.67).
DSRS-ECU inoperable
Replace the SRS-ECU. OK
the driver’s seat belt pre-tensioner>
Measure at the SRS-ECU connector C-41 .
DDisconnect the SRS-ECU connector C-41.
DDisconnect the driver’s seat belt pre-tensioner
D-28*
1and D-26*2.
DMeasure at the harness side
DContinuity between terminal 29 or 30 and
body earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to
avoid a possible decrease in the contact
pressure.
OK:No continuity
NO
Replace the driver’s seat belt pre-tensioner.

MUT-II self-diag code
DConnect the dummy resistor (MB991865) to the resistor harness
(MB991866).
DDisconnect the driver’s seat belt pre-tensioner connector D-28*
1and
D-26*2and insert the resistor harness (MB991866) behind the
harness side connector.
Caution
Do not directly insert a probe or other devices at the front of the
connector to avoid a possible decrease in the contact pressure.
DConnect the negative ( - ) terminal of the battery
DCheck the diagnosis code again after erasing the memory.
Is code No.66 or No.67 output?
YES (when No.67 is output)YES (when No.66 is output)
Replace the SRS-ECU.
the driver’s seat belt pre-tensioner>
Measure at the SRS-ECU connector C-41 .
DDisconnect the SRS-ECU connector C-41.
DDisconnect the driver’s seat belt pre-tensioner
D-28*
1and D-26*2.
DIgnition switch:ON
DMeasure at the harness side
DVoltage between terminal 29 or 30 and body
earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to
avoid a possible decrease in the contact
pressure.
OK:0V
NG
Check connector:D-28*1, D-26*2, C-133*1, C-112*2, C-41
Check the trouble symptoms.
Check the harness between the driver’s seat belt pre-tensioner and the SRS-ECU,
and repair if necessary.
NG
OK
NG
OKResistor harness
(MB991866) Dummy resistor
(MB991865)
resistance (3Ω)
Instrumental panel
wiring harness
Driver’s seat belt
pre-tensioner connector
Connector C-41
Connector C-41
NOTE
*1: L.H. drive vehicles
*2: R.H. drive vehicles

SRS -Troubleshooting52B-40
Code No.68 Front passenger’s seat belt pre-tensioner
(squib) system (short-circuited to power supply)Possible Cause
Code No.69 Front passenger’s seat belt pre-tensioner
(squib) system (short-circuited to earth)
This code is output when the input terminal of the SRS-ECU front passenger’s
seat belt pre-tensioner (squib) is short-circuited to power supply (code No.68) or
short-circuited to earth (code No.69).DHarness or connector fault
DThe harness of the front passenger’s seat belt
pre-tensioner (squib) is short-circuited to power
supply (code No.68) or short-circuited to earth
(code No.69).
DSRS-ECU inoperable
NO
Replace the front passenger’s seat belt pre-tensioner.

MUT-II self-diag code
DConnect the dummy resistor (MB991865) to the resistor harness
(MB991866).
DDisconnect the front passenger’s seat belt pre-tensioner connector
D-28*
1and D-26*2and insert the resistor harness (MB991866)
behind the harness side connector.
Caution
Do not directly insert a probe or other devices at the front of the
connector to avoid a possible decrease in the contact pressure.
DConnect the negative ( - ) terminal of the battery
DCheck the diagnosis code again after erasing the memory.
Is code No.68 or No.69 output?
YES (when No.69 is output)YES (when No.68 is output)
Replace the SRS-ECU.
the front passenger’s seat belt pre-tensioner>
Measure at the SRS-ECU connector C-41 .
DDisconnect the SRS-ECU connector C-41.
DDisconnect the front passenger’s seat belt
pre-tensioner connector D-28*
1and D-26*2.
DIgnition switch:ON
DMeasure at the harness side
DVoltage between terminal 27 or 28 and body
earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to
avoid a possible decrease in the contact
pressure.
OK:0V
NG
Replace the SRS-ECU.
Correct
Check connector:D-28*1, D-26*2, C-133*1, C-112*2, C-41
Check the trouble symptoms.
Check the harness between the front passenger’s seat belt pre-tensioner and the
SRS-ECU, and repair if necessary.OK
the front passenger’s seat belt pre-tensioner>
Measure at the SRS-ECU connector C-41 .
DDisconnect the SRS-ECU connector C-41.
DDisconnect the front passenger’s seat belt
pre-tensioner connector D-28*
1and D-26*2.
DMeasure at the harness side
DContinuity between terminal 27 or 28 and
body earth
Caution
Do not directly insert a probe or other
devices at the front of the connector to
avoid a possible decrease in the contact
pressure.
OK:No continuity
NG
OK
NG
OK
NG
Resistor harness
(MB991866) Dummy resistor
(MB991865)
resistance (3Ω)
Instrumental panel
wiring harness
Front passenger’s seat belt
pre-tensioner connector
Connector C-41 Connector C-41
NOTE
*1: L.H. drive vehicles
*2: R.H. drive vehicles

SRS -Troubleshooting52B-41
INSPECTION CHART FOR TROUBLE SYMPTOMS
Study the trouble symptoms and check according to the inspection procedure chart.
TroubleInspection procedure No(s).Reference page
Communication with MUT-II is impossible.152B-41
SRS warning lamp does not illuminate.See diagnosis code No.43.52B-33
SRS warning lamp does not go out.See diagnosis code No.43, 44.52B-33
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
Inspection Procedure 1
Communication with MUT-II is impossible.
Probable cause
When communication with all systems is impossible, diagnosis circuit is
suspected as faulty.
When only communication with SRS air bags is impossible, open in diagnosis
output circuit or power supply circuit including earth circuit may be present.DHarness, connector malfunction
DSRS-ECU malfunction
DMUT ROM pack unmatching
OKReplace the SRS-ECU.
NG
NG
Check the harness between the SRS-ECU and the ignition
switch IG1, and repair if necessary.
NOCheck the MUT-II diagnosis circuit, and repair if necessary.
OK
Check the trouble symptoms.
NG
Correct
NG
Check the harness between the SRS-ECU and earth, and
repair if necessary.
OK
Check the trouble symptoms.
NG
Correct
OK
OK
Check the trouble
symptoms.
Check the harness between the SRS-ECU and the diagnosis
connector, and repair if necessary.
YES
(1) NG
Check connector:C-21
(2), (3)
NG
Check connector:C-21, C-213, C-210
circuit)>
Measure at the C-21 SRS-ECU connector.
DDisconnect the SRS-ECU connector C-21 and measure at
the harness side.
Caution
Do not directly insert a probe or other devices at the
front of the connector to avoid a possible decrease in
the contact pressure.
(1) Continuity between terminal
7 and body earth
OK:Continuity (2Ωor less)
DConnect the negative ( - ) terminal
of the battery
DIgnition switch:ON
(2) Voltage between terminal 13
and body earth
OK:9 V or more
(3) Voltage between terminal 16
and body earth
OK:9 V or more
NG
Correct
Check connector:C-21, C-26, C-22
Is communication by MUT-II possible when the ignition switch
is ON?
NG
Measure at the SRS-ECU connector C-21 and diagnosis
connector C-22 .
DDisconnect SRS-ECU connector C-21 and measure at the
harness side and diagnosis connector C-22.
DContinuity check between the following terminals
C-21 connector C-22 connector
20 – 7
Caution
Do not directly insert a probe or other devices at the
front of the connector to avoid a possible decrease in
the contact pressure.
OK:Continuity (2Ωor less)
Connector C-21
Connector C-22
Connector C-21
Connector C-21

SRS - SRS Maintenance52B-42
SRS MAINTENANCE
The SRS must be inspected by an authorized dealer 10 years
after the date of vehicle registration.
SRS WARNING LAMP CHECK
Turn the ignition switch to the ON position. Does the SRS
warning lamp illuminate for about 7 seconds, and then go
out? If yes, SRS system is functioning properly. If no, refer
to page 52B-6.
SRS COMPONENT VISUAL CHECK
Turn the ignition key to LOCK (OFF) position, disconnect
the negative ( - ) battery cable and tape the terminal.
Caution
Wait at least 60 seconds after disconnecting the battery
cable before doing any further work. (Refer to P.52B-3.)
SRS CONTROL UNIT (SRS-ECU)
1. Check SRS-ECU case and brackets for dents, cracks,
deformation or rust.
Caution
The SRS may not activate if the SRS-ECU is not
installed properly, which could result in serious injury
or death to the vehicle’s driver or front passenger.
2. Check connector for damage, and terminals for
deformation or rust.
Replace SRS-ECU if it fails visual check.
(Refer to P.52B-50.)
SRS warning lamp
Insulating tape
Battery
Battery
( - ) cable
SRS-ECU

SRS - SRS Maintenance52B-43
AIR BAG MODULES, STEERING WHEEL AND CLOCK
SPRING AND SEAT BELT WITH PRE-TENSIONER
1. Remove the air bag modules, steering wheel and clock
spring. (Refer to P.52B-52.)
Caution
The removed air bag modules should be stored in
a clean, dry place with the cover face up.
2. Check cover for dents, cracks or deformation.
3. Check connector for damage, terminals deformities, and
harness for binds.
4. Check air bag inflator case for dents, cracks or deformities.
5. Check harness and connectors for damage, and terminals
for deformation.
6. Check clock spring connectors and protective tube for
damage, and terminals for deformation.
7. Visually check the clock spring case for damage.
8. Align the mating marks of the clock spring and, after
turning the vehicle’s front wheels to straight-ahead
position, install the clock spring to the column switch.
Mating Mark Alignment
Turn the clock spring clockwise fully, and then turn back
it approx. 3 times counterclockwise to align the mating
marks.
Caution
If the clock spring’s mating mark is not properly
aligned, the steering wheel may not be completely
rotational during a turn, or the flat cable within the
clock spring may be severed, obstructing normal
operation of the SRS and possibly leading to serious
injury to the vehicle’s driver or front passenger.
9. Install the steering column covers, steering wheel and
the air bag module.
10. Check steering wheel for noise, binds of difficult operation.
11. Check steering wheel for excessive free play.Inflator
Connector
Connector
Steering
wheel - driver’s
air bag module
assembly



Connector Inflator case
Mating marks

SRS - SRS Maintenance52B-44
REPLACE ANY VISUALLY INSPECTED PART IF IT
FAILS THAT INSPECTION. (Refer to P.52B-52.)
Caution
The SRS may not activate if any of the above
components is not installed properly, which could
result in serious injury or death to the vehicle’s driver
or front passenger.
INSTRUMENT PANEL WIRING HARNESS
Instrument panel wiring harness
1. Check connector for poor connection.
2. Check harnesses for binds, connectors for damage, and
terminals for deformation.
REPLACE ANY CONNECTORS OR HARNESS THAT
FAIL THE VISUAL INSPECTION. (Refer to P.52B-3.)
Caution
The SRS may not activate if SRS harnesses or
connectors are damaged or improperly connected,
which could result in serious injury or death to the
vehicle’s driver or front passenger.
POST-INSTALLATION INSPECTION
Reconnect the negative battery terminal. Turn the ignition
switch to the ON position. Does the SRS warning lamp
illuminate for about 7 seconds, and then go out? If yes, SRS
system is functioning properly. If no, consult page 52B-6.
SRS warning lamp