2
INSPECTION
· Check the SRS-ECU and brackets for dents, cracks or
deformation.
· Check connectors and lock lever for damage, and
terminals for deformation
Caution
If a dent, crack, deformation or rust is discovered,
replace the SRS-ECU with a new one.
NOTE
For checking of the SRS-ECU other than described
above, refer to the section concerning troubleshooting.
(Refer to P.52B-5.)
AIR BAG MODULES AND CLOCK SPRING
Caution
1. Disconnect the 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. (Refer to P.52B-3)
2. Never attempt to disassemble or repair the
air bag modules or clock spring.
If faulty, replace it.
3. do not drop the air bag modules or clock
spring or allow contact with water, grease
or oil.
Replace it if a dent, crack, deformation or
rust is detected.4. The air bag modules should be stored on a
flat surface and placed so that the pad
surface is facing upward.
Do not place anything on top of it.
5. Do not expose the air bag modules to
temperatures over 93° C.
6. After deployment of an air bag, replace the
clock spring with a new one.
7. Wear gloves and safety glasses when
handling air bags that have already
deployed.
8. An undeployed air bag module should only
be disposed of in accordance with the
procedures (Refer to P.52B-31.)
52B-22SRS - SRS-ECU/Air Bag Modules and Clock Spring
52400220031
After deployment of an air bag, replace the
air bag modules. Check the clock spring,
and if faulty, replace it with a new part.
52400240044
4
INSPECTION
· Check the SDU and brackets for dents, cracks or
deformation.
· Check connector for damage, and terminals for
deformation
Caution
If a dent, crack, deformation or rust is discovered,
replace the SDU with a new one.
NOTE
For checking of the SDU other than described above,
refer to the section concerning troubleshooting. (Refer to
P.52B-6.)
AIR BAG MODULES AND CLOCK SPRING
Caution
1. Disconnect the 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. (Refer to P.52B-3)
2. Never attempt to disassemble or repair the
air bag modules or clock spring.
If faulty, replace it.
3. do not drop the air bag modules or clock
spring or allow contact with water, grease
or oil.
4. Replace it if a dent, crack, deformation or
rust is detected.
4. The air bag modules should be stored on a
flat surface and placed so that the pad
surface is facing upward.
Do not place anything on top of it.
5. Do not expose the air bag modules to
temperatures over 93° C.
6. After deployment of an air bag, replace the
clock spring with a new one.
7. Wear gloves and safety glasses when
handling air bags that have already
deployed.
8. An undeployed air bag module should only
be disposed of in accordance with the
procedures (Refer to P.52B-31.)
52B-28SRS - SRS Diagnosis Unit (SDU)/Air Bag Modules and Clock Spring
52400220093
After deployment of an air bag, replace the
air bag modules. Check the clock spring, and
if faulty, replace it with a new part.
52400240143
5
TEST 2 SRS WARNING LAMP DOES NOT ILLUMINATE
(1) Read (and write down) all of the displayed diagnosis codes
and service data (fault duration and how many times
memories are erased) using the Multi- use Tester
NOTE
(1) if the Multi-use Tester or Mut-II displays “CAN’T
COMM”. check the Multi-use Tester or MUT-II and
vehicle side diagnosis connector for poor connections
(Refer to P.52B-12.) and perform TEST 4.
(2) Maximum stored period: 9999 minutes (approximately
7 days)
(3) Maximum number of times to be stored: 250
(4) Check diagnosis codes against SELF-DIAGNOSIS QUICK
REFERENCE CHART and perform service indicated there.
SELF-DIAGNOSIS QUICK REFERENCE CHART
After carrying out test 1 or 2, use the following table to repair.
Diagnosis
code No.Explanation Service
- Normal. The SRS is in good order -
11The circuits for the front impact sensor are shorted together, the (-) side of
the harness between the air bag module and the SDU is shorted to the
earth, or the (+) side of the harness between the front impact sensor and
the SDU is shorted to the earthPerform TEST 5
air bag> L.H. drive vehicles
refer to P 52B-22
12Right or left impact sensor circuit is open, or the wire from the sensor to the
SDU is open-circuit.R.H. drive vehicles: refer to
P. 52B-26
to the SDU are open-circuitFront passenger’s air bag>
refer to P.52B-32
21The circuits for the driver’s side air bag module (squib) are shorted together
other or the circuit is earthed.Perform TEST 6
air
22The driver’s side air bag module (squib) circuit is open or the wire from the
driver’s side air bag module to the SDU (clock spring) is open circuit, the
harness connection is defective, or the (+) side of the harness between the
driver’s side air bag module and the SDU is shorted to the earth.
Disconnected connector in driver’s side air bag module (squib).
Open-circuit in clock spring due to inappropriate neutral position.bag> L.H. drive vehicles:
refer to P52B-35 R.H. drive
vehicles refer to P.52B-39
to P.52B-45
24The circuits for the front passenger’s side air bag module (squib) are
shorted together other or the circuit is earthed.Perform TEST 13
(Refer to P.52B-64)
25The front passenger’s side air bag module (squib) circuit is open or the wire
from the front passenger’s side air bag module to the SDU (clock spring) is
open circuit, the harness connection is defective or the (+) side of the
harness between the front passenger’s side air bag module and the SDU is
shorted to the earth.
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting52B-14
6
TEST 2 SRS WARNING LAMP DOES NOT ILLUMINATE
(1) Read (and write down) all of the displayed diagnosis codes
and service data (fault duration and how many times
memories are erased) using the Multi-use Tester <1993
models> or MUT-II
NOTE
(1) if the Multi-use Tester or Mut-II displays “CAN’T
COMM”. check the Multi-use Tester or MUT-II and
vehicle side diagnosis connector for poor connections
(Refer to P.52B-10.) and perform TEST 4.
(2) Maximum stored period: 9999 minutes (approximately
7 days)
(3) Maximum number of times to be stored: 250
(4) Check diagnosis codes against SELF-DIAGNOSIS QUICK
REFERENCE CHART and perform service indicated there.
SELF-DIAGNOSIS QUICK REFERENCE CHART
After carrying out test 1 or 2, use the following table to repair.
Diagnosis
code No.Explanation Service
- Normal. The SRS is in good order -
11 The circuits for the front impact sensor are shorted together, the (-) side of
the harness between the air bag module and the SDU is shorted to the
earth, or the (+) side of the harness between the front impact sensor and
the SDU is shorted to the earthPerform TEST 5
air bag> refer to P 52B-20
SDU is open-circuit.passenger’s air bag>
refer to P.52B-24
13 Right and left impact sensor circuits are open or the wires from the sensors
to the SDU are open-circuit
21 The circuits for the driver’s side air bag module (squib) are shorted together
other or the circuit is earthed.Perform TEST 6
air
22 The driver’s side air bag module (squib) circuit is open or the wire from the
driver’s side air bag module to the SDU (clock spring) is open circuit, the
harness connection is defective, or the (+) side of the harness between the
driver’s side air bag module and the SDU is shorted to the earth.
Disconnected connector in driver’s side air bag module (squib).
Open-circuit in clock spring due to inappropriate neutral position.bag> refer to P52B-27
to P.52B-31
24 The circuits for the front passenger’s side air bag module (squib) are
shorted together other or the circuit is earthed.Perform TEST 13
(Refer to P.52B-47)
25 The front passenger’s side air bag module (squib) circuit is open or the wire
from the front passenger’s side air bag module to the SDU (clock spring) is
open circuit, the harness connection is defective or the (+) side of the
harness between the front passenger’s side air bag module and the SDU is
shorted to the earth.
52B-12SUPPLEMENT RESTRAINT SYSTEM (SRS) - Troubleshooting
10
TROUBLESHOOTING
INSPECTION CHART FOR DIAGNOSIS CODES
Inspect according to the inspection chart that is appropriate for the malfunction code.
Code No. Diagnosis item Reference page
14 Analog G-sensor system in the SRS-ECU -
15, 16 Safing G-sensor system in the SRS-ECU -
21, 22, 61, 62 Driver’s side air bag module (squib) system 52B-5
24, 25, 64, 65 Front passenger’s side air bag module (squib) system 52B-6
31, 32 SRS-ECU capacitor system -
34* Connector lock system -
35 SRS-ECU capacitor system -
41* IG1 (A) power circuit system 52B-7
42* IG1 (B) power circuit system 52B-7
43 SRS warning lamp drive circuit system Lamp does not illuminate. * 52B-7
Lamp does not switch off. -
44 SRS warning lamp drive circuit system -
45 SRS-ECU non volatile memory (EEPROM) and A/D converter system -
51, 52 Driver’s side air bag module (squib ignition drive circuit) system -
54, 55 Front passenger’s side sir bag module (squib ignition drive circuit) system -
NOTE
(1) *: if the vehicle condition return to normal, the diagnosis code will be automatically erased, and the SRS warning
lamp will return to normal.
(2) If the vehicle has a discharged battery it will store the fault codes 41 or 42. When these diagnosis codes are
displayed, check the battery.
INSPECTION PROCEDURE CLASSIFIED BY DIAGNOSIS CODE
Code No. 21,22, 61 or 62 Driver’s side air bag module
(squib) systemProbable cause
These diagnosis codes are output if there is abnormal resistance between the
input terminals of the driver’s side air bag module (squib).
The trouble causes for each diagnosis code No. are as follows.·
Malfunction of clock spring
·
Open-circuit in clock spring due to inappropriate neutral
position.
·
Malfunction of wiring harnesses or connectors
·
Malfunction of driver’s side air bag module (squib)
·
Malfunction of SRS-ECU
Code No. Trouble symptoms
21
·
Short in driver’s side air bag module (squib) or harness short
·
Short in clock spring
22
·
Open circuit in driver’s side air bag module (squib) or open harness
·
Open circuit in clock spring
·
Disconnected connector in the driver’s side air bag module (squib).
·
Open circuit in clock spring due to inappropriate neutral position.
·
Malfunction of connector contact
61
·
Short in driver’s side air bag module (squib) harness leading to the power supply
62
·
Short in driver’s side air bag module (squib) harness leading to the earth
52B-5SRS - Troubleshooting
14
TEST 2 SRS WARNING LAMP DOES NOT ILLUMINATE
(1) Read (and write down) all of the displayed diagnosis codes
and service data (fault duration and how many times
memories are erased) using the MUT or MUT-II
NOTE
(1) if the MUT or MUT-II displays “CAN’T COMM”. check
the MUT or MUT-II and vehicle side diagnosis
connector for poor connections (Refer to P.52B-7.) and
perform TEST 6.
(2) Maximum stored period: 9999 minutes (approximately
7 days)
(3) Maximum number of times to be stored: 250
(4) Check diagnosis codes against SELF-DIAGNOSIS QUICK
REFERENCE CHART and perform service indicated there.
SELF-DIAGNOSIS QUICK REFERENCE CHART
After carrying out test 2 or 3, use the following table to repair.
Diagnosis
code No.Explanation Service
- Normal. The SRS is in good order -
14 Analog G sensor output signal is abnormal
Analog G sensor does not function or its characteristic is abnormalReplace the SDU
(Refer to P.52B-34.)
15 The circuits for the safing impact sensor are shorted together or the circuit
is earthed
16 The safing input sensor circuit is open or the wire from the air module to the
SDU is open circuit
21 The circuits for the air bag module (squib) are shorted together other or the
circuit is earthed.Perform TEST 7
22 The air bag module (squib) circuit is open or the wire from the air bag
module to the SDU (clock spring) is open circuit, the harness connection is
defective, or the (+) side of the harness between the air bag module and
the SDU is shorted to the earth.
Disconnected connector in driver’s side air bag module (squib).
Open-circuit in clock spring due to inappropriate neutral position.
31 The DC/DC converter (integrated in the SDU) terminal voltage is higher
than the specified value for 5 seconds.Replace the SDU
(Refer to P.52B-34.)
52B-9SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
15
INSPECTION PROCEDURE CLASSIFIED BY DIAGNOSTIC TROUBLE
Code No. 14 Analog G-sensor system in the SDU Probable cause
(Comment)
The SDU monitors the output of the analog G sensor inside the SDU. It outputs this
code when any of the following are detected
·
When the analog G sensor is not operating
·
When the characteristics of the analog G sensor are abnormal·
Malfunction of SDU
The cause is probably a malfunction of the analog G-sensor inside the SDU, so replace the SDU
Code No. 15 or 16Safing G-sensor system in the SDU Probable cause
(Comment)
This code is output if the resistance between the terminals of the safing G sensor
inside the SDU is different from normal.
The trouble causes for each diagnosis code No. are as follows·
Malfunction of SDU
Code No. Trouble symptom
15 Short circuit in the safing G-sensor
16 Open circuit in the safing G-sensor
Code No. 21 or 22 Driver’s side Air bag module (squib) system Probable cause
(Comment)
These diagnosis codes are output if there is abnormal resistance between the input
terminals of the air bag module (driver’s side squib).
The trouble causes for each code No. are as follows·
Malfunction of clock spring
·
Open-circuit in clock spring due to inappropriate neutral
position
·
Malfunction of harnesses or connectors
·
Malfunction of air bag module (driver’s side squib)
·
Malfunction of SRS-ECU
Code No. Trouble Symptom
21·
Short in air bag module (driver’s side squib) or harness short
·
Short in clock spring
22·
Open circuit in Air bag module (driver’s side squib) or harness
·
Open circuit in clock spring
·
Disconnected connector in the driver’s side air bag module (squib)
·
Open-circuit in clock spring due to inappropriate neutral position
·
Malfunction of connector contact
SRS - Troubleshooting52B-8
21
INSPECTION PROCEDURE CLASSIFIED BY DIAGNOSTIC TROUBLE
Code No. 14 Analog G-sensor system in the SRS-ECU Probable cause
The SRS-ECU monitors the output of the analog G-sensor inside the SRS-ECU. It
outputs this code when any of the following are detected
·
When the analog-G sensor is not operating
·
When the characteristics of the analog-G sensor are abnormal
·
When the output from the analog G-sensor is abnormal·
Malfunction of SRS-ECU
Replace the SRS-ECU
Code No.15 or 16 Safing G-sensor system in the SRS-ECU Probable cause
This code is output if there is a short or open circuit between the terminals of the
safing G-sensor inside the SRS-ECU.
The trouble causes for each diagnosis code No. Are as follows·
Malfunction of SRS-ECU
Code No. Trouble Symptom
15 Short circuit in the safing G-sensor
16 Open circuit in the safing G-sensor
Replace the SRS-ECU
Code No. 21, 22 or 61 Air bag module (driver’s side squib)
systemProbable cause
These diagnosis codes are output if there is abnormal resistance between the input
terminals of the air bag module (driver’s side squib).
The trouble causes for each code No. are as follows·
Malfunction of clock spring
·
Open-circuit in clock spring due to inappropriate neutral
position
·
Malfunction of harnesses or connectors
·
Malfunction of air bag module (driver’s side squib)
·
Malfunction of SRS-ECU
SRS - Troubleshooting52B-6