Page 1274 of 1449

SRS -Troubleshooting52B-30
Code No.41 Power supply circuit system (fuse No.2
circuit)Possible Cause
This codes output when the voltage between terminal IG1(SRS-ECU, terminal
No.16) and earth has been below the standard value for 5 seconds.
However, code No.41 is automatically erased and SRS warning lamp goes out
when a normal operation is resumed. If code No.41 and 42 are output at the
same time, check the battery first since the battery voltage may have decreased.DHarness or connector fault
DSRS-ECU inoperable
block and the combination meter>
Measure at the junction block connector
C-213.
DDisconnect the junction block connector
C-213 and measure at the harness
side.
DContinuity check between terminal 25
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
block>
Measure at the junction block connector C-213.
DDisconnect the junction block connector C-213 and
measure at the harness side.
DContinuity check between terminal 24 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
NGCorrect the harness between the junction block and
combination meter (SRS warning lamp).
NGOK
NGNG
Check the trouble symptoms.Correct
Check the harness between the SRS-ECU and the ignition
switch IG
1, and repair if necessary. Fuse is normal
NG
Fuse disconnection
Check the junction block general fuse No.2.
Fuse disconnection
Check when fuse disconnects
DReplace the fuse.
DTurn the ignition switch to the ON position and then turn it
to the OFF position after one minute or more has passed.
Check the fuse.
OK
OK
Replace the SRS-ECU.
>Measure at the SRS-ECU connector C - 21.
DDisconnect the SRS-ECU connector C-21.
DConnect the negative ( - ) terminal of the battery
DIgnition switch: ON
DMeasure at the harness side
DVoltage between terminal 16 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:9 V or more
Check the other circuits using the general fuse No.2.
(See the Electrical Wiring Diagram.) OK
Check connector:C-21, C-213, C-210
Go to Next PageConnector C-21
Connector C-213
Connector C-213
Page 1275 of 1449
SRS -Troubleshooting52B-31
block>
Measure at the SRS - ECU connector C-21.
DDisconnect the SRS-ECU connector C-21 and measure at
the harness side.
DContinuity check between terminal 16 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
Connector C-41
OK
Check the harness between the SRS-ECU and junction block,
and repair if necessary.
Replace the SRS-ECU.NG
NG
From Previous Page
Page 1276 of 1449

SRS -Troubleshooting52B-32
Code No.42 Power supply circuit system (fuse No.3
circuit)Possible Cause
This code is output when the voltage between terminal IG1(SRS-ECU, terminal
No.13) and earth has been below the standard value for 5 seconds.
However, code No.42 is automatically erased and SRS warning lamp goes out
when a normal operation is resumed.If code No.41 and 42 are output at the
same time, check the battery first since the battery voltage may have decreased.DHarness or connector fault
DSRS-ECU inoperable
OK
Check the other circuits using the general
fuse No.3. (See the Electrical Wiring
Diagram.)
NGOK
NG
NG
NG
Check connector:C-21, C-213, C-210
Check the trouble
symptoms.Correct
Check the harness between the SRS-ECU and the ignition
switch IG
1, and repair if necessary.
NG
Fuse disconnection
Fuse disconnection
OK
Replace the SRS-ECU.
switch IG
1
>Measure at the SRS-ECU connector C - 21.
DDisconnect the SRS-ECU connector C-21 and measure at
the harness side.
DConnect the negative ( - ) terminal of the battery
DIgnition switch: ON
DVoltage between terminal 13 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:9 V or more
OK
Check the harness between the SRS-ECU and junction block,
and repair if necessary.
block>
Measure at the C-21 SRS-ECU connector.
DDisconnect the SRS-ECU connector C-21 and measure at
the harness side.
DContinuity check between terminal 13 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
Replace the SRS-ECU.Fuse is normal
Check the junction block general fuse No.3.
Check when fuse disconnects
DReplace the fuse.
DTurn the ignition switch to the ON position and then turn it
to the OFF position after one minute or more has passed.
Check the fuse.
block>
Measure at the junction block connector C-213.
DDisconnect the junction block connector C-213 and
measure at the harness side.
DContinuity check between terminal 7 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 continuityConnector C-21
Connector C-213
Connector C-21
Page 1278 of 1449
SRS -Troubleshooting52B-34
Code No.61 Driver’s air bag module (squib) system
(short-circuited to power supply)Possible Cause
Code No.62 Driver’s air bag module (squib) system
(short-circuited to earth)
This code is output when the input terminal of the SRS-ECU driver’s air bag
module (squib) is short-circuited to power supply (code No.61) or short-circuited
to earth (code No.62).DClock spring fault
DHarness or connector fault
DThe harness of the driver’s air bag module (squib)
is short-circuited to power supply (code No.61) or
short-circuited to earth (code No.62)
DSRS-ECU inoperable
NOTE
Two different types of driver’s air bag modules by model are featured. Thus, two types of air bag module
by model are described in the following flowchart.
RS: Steering wheel and air bag module separate type
RS-II: Steering wheel and air bag module incorporate type
Page 1279 of 1449

SRS -Troubleshooting52B-35
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
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
MUT-II self-diag code
DRelease the clock spring connector (2 - pin) C-204.
DConnect the dummy resistor (MB991865) to the resistor harness
(MB991866).
DInsert the resistor harness
(MB991866) behind the harness side connector C-204.
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.61 or No.62 output?
YES (when No.62 is output)YES (when No.61 is output)NO
Check the clock spring (Refer to P.52B-59.)
NOYES
Replace the clock spring.Replace the driver’s air bag module
(squib).
Replace the SRS-ECU.
NG
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.
NG
OK
NG
OK
NG
Connector C-21Connector C-21 Resistor harness
(MB991866)
C - 204 clock spring
harness side connector Dummy resistor
(MB991865)
resistance (3Ω)
Replace the SRS-
ECU. OK
Page 1280 of 1449

SRS -Troubleshooting52B-36
MUT-II self-diag code
DDisconnect the clock spring connector No.1 (connector connected with
the air bag module).
DConnect the dummy resistor (MB991865) to the resistor harness
(MB991866).
DInsert the resistor harness (MB991866) behind the clock spring
connector No.1.
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.61 or No.62 output?
YESNO
Replace the driver’s air bag module (squib).
MUT-II self-diag code
DRelease the clock spring connector (2 - pin) C-204 .
DConnect the dummy resistor (MB991865) to the resistor harness
(MB991866).
DInsert the resistor harness
(MB991866) behind the harness side connector C-204.
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.61 or No.62 output?
YES (when No.62 is output)
Go to Next Page
YES (when No.61 is output)Resistor harness
(MB991866) Dummy resistor
(MB991865)
resistance (3Ω)
1
NO
Replace the clock spring.
Resistor harness
(MB991866)
C - 204 clock spring
harness side connector Dummy resistor
(MB991865)
resistance (3Ω)
Page 1281 of 1449

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
Page 1286 of 1449

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