Page 1259 of 1449

SRS -Troubleshooting52B-15
OKNG
spring>
Measure at the SRS-ECU connector C - 21 .
DDisconnect the SRS-ECU connector C-21.
DRelease the the clock spring connector C-204.
Caution
Disconnect the connector and short-circuit the squib
circuit before releasing the short bar of the SRS-ECU
connector in the following operation.
DCable bands between terminals 11, 12 and the short bar
(width:3 mm, thickness:0.5 mm) between terminals 11 and
12 and the short bar, and release the short bar.
(See Figure A.)
Caution
As the short bar may not be releasable if inserted
insufficiently, insert more than 4 mm.
DMeasure at the harness side
DContinuity check between terminals 11 and 12
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.
Figure A
Terminal
Short bar
Front view of SRS-ECU
connector C-21
(harness side)
Cable band and etc.Section
A-A
4 mm or more
A
A
Connector C-21
YES
From Previous Page
Check the harness between the clock spring and the
SRS-ECU, and repair if necessary.
Check connector: C - 21, C-204
Check the trouble
symptoms.
NG
CorrectOK
NG
Page 1260 of 1449
SRS -Troubleshooting52B-16
Code No.22 Driver’s air bag module (squib) systemPossible Cause
This code is output when open circuit occurs in the SRS-ECU driver’s air bag
module (squib) circuit.
However, SRS warning lamp goes out when a normal operation is resumed
(diagnosis code is not cleared.)DOpen in the clock spring
DHalf open in the circuit due to improper neutral
positioning of the clock spring
DOpen in the driver’s air bag module (squib) circuit
DDriver’s air bag module (squib) connector falling
out
DConnector improper contact
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 1261 of 1449

SRS -Troubleshooting52B-17
spring>
Measure at the SRS-ECU connector C-21 and the clock
spring connector C-204.
DDisconnect the SRS-ECU connector C-21 and the clock
spring connector C-204 and measure at the harness side.
DContinuity check between the following terminals
Connector C-21 Connector C-204
11 – 2
12 – 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.
OK:Continuity (2Ωor less)
NG
Correct
Check connector:C-21, C-204
OK
Check the trouble
symptoms.
NG
Check the harness between the clock spring and the
SRS-ECU, and repair if necessary. NG
Connector C-21Connector C-204
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.22 output?
YES
Check the clock spring (Refer to P.52B-59.)
NOYES
Replace the clock spring.Replace the driver’s air bag module
(squib).NO
Replace the SRS-ECU.
OK Resistor harness
(MB991866)
Clock spring harness
side connector C - 204 Dummy resistor
(MB991865)
resistance (3Ω)
Page 1262 of 1449

SRS -Troubleshooting52B-18
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.22 output? Dummy resistor
(MB991865)
resistance (3Ω)
1
YESNO
Replace the steering wheel - driver’s air bag module assembly. Resistor harness
(MB991866)
Go to Next Page
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.22 output?
YES
Replace the clock spring.NO
Resistor harness
(MB991866)
C-204 clock spring
harness side connector Dummy resistor
(MB991865)
resistance (3Ω)
Page 1263 of 1449
SRS -Troubleshooting52B-19
spring>
Measure at the C-21 SRS-ECU connector and C-204 clock
spring connector.
DDisconnect the SRS-ECU connector C-21 and the clock
spring connector C-204 and measure at the harness side.
DContinuity check between the following terminals
C-21 connector C-204 connector
11 – 2
12 – 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.
OK:Continuity (2Ωor less)
NG
Correct
Check connector:C-21, C-204
OK
Check the trouble
symptoms.
NG
Check the harness between the clock spring and the
SRS-ECU, and repair if necessary.
YES
From Previous Page
NG
Connector C-21Connector C-204
Replace the SRS-ECU.
OK
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)