
SUPPLEMENTAL RESTRAINT SYSTEM 9J–10
Accident With Deployment – Component
Replacement And Inspections
Certain SRS components must be replaced or inspected
for damage after a frontal crash involving air bag
deployment. Those components are:
Air bag assembly
SDM
CAUTION: Refer to “SDM Replacement Guidelines”
below for important information on SDM
replacement in both deployment and non
deployment crashes.
SRS coil assembly — Inspect wiring and connector
for any signs of scorching, melting, or damage due to
excessive heat. Replace if damaged. Refer to
section “SRS Coil Assembly” in this manual.
Accident With or Without Deployment –
Component Inspection
Certain SRS system components and rotation parts must
be inspected after any crash, whether the air bag
deployed or not. Those components are:
Steering column — Refer to Inspection Required
“After an Accident” in this manual.
Knee bolsters and mounting points — Inspect for any
distortion, bending, cracking, or other damage.
I/P steering column reinforcement plate — Inspect for
any distortion, bending, cracking, or other damage.
I/P braces — Inspect for any distortion, bending,
cracking, or other damage.
Seat belts and mounting points — Refer to “Seat
Belts” in Section “Seat Belt” of this workshop manual.
SDM Replacement Guidelines
SDM replacement policy requires replacement of SDM,
after crash involving air bag deployment when “SRS
Warning Lamp” turn “ON”, “SRS Diagnosis” should be
done according to Section “Restraint Control System.”
If accident without deployment air bag, it is not necessary
replacement of SDM when do not indicate to replace the
SDM by scan tool after SRS system check.
Wiring Damage
If any SRS wire harness is damaged, it should be
replaced. Don’t repair SRS harness. It is replace only.
SRS Connector (Plastic Body And
Terminal Metal Pin) Damage
If any connector or terminal in the SRS wire harness
(except pigtails) is damaged, it should be replaced.
SRS Wire Pigtail Damage
If the wiring pigtail (a wire or wires attached directly to the
device, not by a connector) is damaged, the entire
component (with pigtail) must be replaced. Examples of
“pigtail” components are the driver air bag assembly, the
passenger air bag assembly, and the SRS coil assembly.
On–Vehicle Service
Service Precaution
WARNING: WHEN PERFORMING SERVICE ON OR
AROUND SRS COMPONENTS OR SRS WIRING,
FOLLOW THE PROCEDURES LISTED BELOW TO
TEMPORARILY DISABLE THE SRS. FAILURE TO
FOLLOW PROCEDURES COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY OR OTHERWISE UNNEEDED SRS REPAIRS.
The SDM in Driver–Passenger SRS can maintain
sufficient voltage to cause a deployment for up to 15
seconds after the ignition switch is turned “OFF,” the
battery is disconnected, or the fuse powering the SDM is
removed.
Many of the service procedures require removal of the
“C–21” fuse, and disconnection of the air bag assembly
from the deployment loop to avoid an accidental
deployment. If the air bag assembly is disconnected from
the deployment loop as noted in the “Disabling the SRS”
procedure that follows, service can begin immediately
without waiting for the 15 second time period to expire.
Disabling The SRS
Removal
Turn the ignition switch to “LOCK” and remove key.
1. Remove SRS fuse C–21, from left dash side lower
fuse block or disconnect battery.
2. Disconnect yellow 2–pin connector at the base of
steering column.
3. Remove glove box assembly, refer to “Passenger Air
Bag Assembly Replacement” in this manual.
4. Disconnect yellow 2–pin connector behind the glove
box assembly.
CAUTION: With the “C–21” fuse removed and
ignition switch “ON”, the “AIR BAG” warning lamp
will be “ON”. This is normal operation and does not
indicate an SRS malfunction.
Enabling The SRS
Installation
CAUTION: Never use the air bag assembly from
another vehicle. Use only the air bag assembly for
Trooper.
Turn ignition switch to “LOCK” and remove key.
1. Connect yellow 2–pin connector passenger air bag
assembly.
2. Install glove box assembly. Refer to “Passenger air
bag assembly replacement” in this manual.
3. Connect yellow 2–pin connector at the base of
steering column.
4. Install “AIR BAG” fuse C–21 to left dash side lower
fuse block or connect battery.
Turn ignition switch to “ON” and verify that the “AIR BAG”
warning lamp turn on 3.5 seconds and then turns “OFF.” If
it does not operate as described, perform the “SRS
Diagnostic System Check” in this manual.

SUPPLEMENTAL RESTRAINT SYSTEM 9J–26
Special Tools
WARNING: TO AVOID DEPLOYMENT WHEN
TROUBLESHOOTING THE SRS, DO NOT USE
ELECTRICAL TEST EQUIPMENT SUCH AS A
BATTERY–POWERED OR AC–POWERED
VOLTMETER, OHMMETER, ETC., OR ANY TYPE OF
ELECTRICAL EQUIPMENT OTHER THAN THAT
SPECIFIED IN THIS MANUAL. DO NOT USE A
NONPOWERED PROBE–TYPE TESTER.
INSTRUCTIONS IN THIS MANUAL MUST BE
FOLLOWED CAREFULLY, OTHERWISE PERSONAL
INJURY MAY RESULT.
5–8840–2421–0 SRS Driver/Passenger
Load Tool
901RS146The SRS Driver/Passenger Load Tool 5–8840–2421–0 is
used only when called for in this section. It is used as a
diagnostic aid and safety device to prevent inadvertent air
bag assembly deployment.
The load tool has three yellow connectors attached to its
case.
The three small connectors are electrically functional and
serve as resistive load substitutions.
No more than two connectors are used at any time. One
of the small connectors is used to substitute for the load of
the driver air bag assembly when it is connected at the top
of the column to the SRS coil assembly. Another small
connector is used to substitute for the load of the driver air
bag assembly and the SRS coil assembly when it is
connected at the base of the column to the SRS wiring
harness. The third small connector is used to substitute
for the load of the passenger air bag assembly and
pretensioner seat belt assembly when connected to the
passenger air bag assembly and pretensioner seat belt
assembly harness connector.
By substituting the resistance of the load tool when called
for, a determination can be made as to whether an inflator
circuit component is causing system malfunction and
which component is causing the malfunction. The loadtool should be used only when specifically called for in the
diagnostic procedures.
NOTE: If comand to use 5–8840–2421–0 load tool when
repair the pretensioner seat belt, connect load tool
connector to use for driver air bag and/or passenger air
bag connector.
5–8840–0285–0 DVM
901RS153The 5–8840–0285–0 DVM is the preferred DVM for use in
SRS diagnosis and repair. However, 5–8840–0366–0
may be used if 5–8840–0285–0 is not available. No other
DVMs are approved for SRS diagnosis and repair.
Scan Tool
901RW176The Tech 2 is used to read and clear SRS Diagnostic
Trouble Codes (DTCs). Refer to the Tech 2 Operators,
Manual for specific information on how to use the Tech 2.

SUPPLEMENTAL RESTRAINT SYSTEM 9J–30
Service Precautions for SRS
Component Service
CAUTION: When fasteners are removed, always
reinstall them at the same location from which they
were removed. If a fastener needs to be replaced, use
the correct part number fastener for that application.
If the correct part number fastener is not available, a
fastener of equal size and strength (or stronger) may
be used. fasteners that are not reused, and those
requiring thread locking compound will be called
out. The correct torque value must be used when
installing fasteners that require it. If the above
conditions are not followed, parts or system damage
could result.
WARNING: WHEN PERFORMING SERVICE ON OR
AROUND SRS COMPONENTS OR SRS WIRING,
FOLLOW THE PROCEDURES LISTED BELOW TO
TEMPORARILY DISABLE THE SRS. FAILURE TO
FOLLOW PROCEDURES COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY OR OTHERWISE UNNEEDED SRS REPAIRS.
The SDM in Driver–Passenger SRS can maintain
sufficient voltage to cause a deployment for up to 15
seconds after the ignition switch is turned “OFF,” the
battery is disconnected, or the fuse powering the SDM is
removed.
Many of the service procedures require removal of the
“C–21” fuse, and disconnection of the air bag assembly
from the deployment loop to avoid an accidental
deployment. If the air bag assembly is disconnected from
the deployment loop as noted in the “Disabling the SRS”
procedure that follows, service can begin immediately
without waiting for the 15 second time period to expire.
Disabling The SRS
Removal
Turn the ignition switch to “OFF” and turn the steering
wheel so that the vehicle’s wheels are pointing straight
ahead.
1. Remove SRS fuse “C–21” from left dash side lower
fuse block or disconnect battery.
2. Disconnect yellow 2–pin connector at the base of
steering column.
3 . R e m o v e g l o v e b o x a s s e m b l y ; R e f e r t o “ P a s s e n g e r a i r
bag assembly replacement” in this section.
4. Disconnect passenger air bag assembly yellow 2–pin
connector behind the glove box assembly.
CAUTION: W i t h t h e “ C – 2 1 ” f u s e r e m o v e d a n d
ignition switch “ON,” the “AIR BAG” warning lamp
will be “ON.” This is normal operation and does not
indicate an SRS malfunction.
Enabling The SRS
Installation
Turn ignition switch to “LOCK” and remove key.
1. Connect yellow 2–pin connector passenger air bag
assembly.2. Install glove box assembly. Refer to “Passenger Air
Bag Assembly Replacement” in this section.
3. Connect yellow 2–pin connector at the base of the
steering column.
4. Install “AIR BAG” fuse “C–21” to left dash side lower
fuse block or connect battery.
Turn ignition switch to “ON” and verify that the “AIR BAG”
warning lamp turn on 3.5 seconds and then turns “OFF.” If
it does not operate as described, perform the “SRS
Diagnostic System Check” in this section.
Handling / Installation / Diagnosis
1. Air bag assembly should not be subjected to
temperatures above 93
C (200F).
2. Air bag assembly, and SDM should not be used if they
have been dropped from a height of 100 centimeters
(3.28 feet) or more.
3. When a SDM is replaced, it must be oriented with the
arrow on the SDM pointing toward the front of the
vehicle. It is very important for the SDM to be located
flat on the mounting surface, parallel to the vehicle
datum line. It is important that the SDM mounting
surface is free of any dirt or other foreign material.
4. Do not apply power to the SRS unless all components
are connected or a diagnostic chart requests it, as
this will set a diagnostic trouble code.
5. The “SRS Diagnostic System Check” must be the
starting point of any SRS diagnostics. The “SRS
Diagnostic System Check” will verify proper “AIR
BAG” warning lamp operation and will lead you to the
correct chart to diagnose any SRS malfunctions.
Bypassing these procedures may result in extended
diagnostic time, incorrect diagnosis, and incorrect
parts replacements.
Inspections Required After An Accident
CAUTION: C e r t a i n S R S c o m p o n e n t s m u s t b e
replaced after a frontal crash involving air bag
deployment.
In all types of accidents regardless of “Air Bag”
deployment, visually inspect all of the following
components and replace as required:
— Driver air bag assembly
— Passenger air bag assembly
— Driver pretensioner assembly
— Passenger pretensioner assembly
— Steering wheel
— SRS coil assembly
— Steering column
— Knee bolster and instrument panel mounting
attachments
— Driver seat and belt
— Passenger seat and belt
—SDM
SDM always should be checked according to “SDM
Replacement Guidelines.”

SUPPLEMENTAL RESTRAINT SYSTEM9J–31
CAUTION: Refer to “SDM Replacement Guidelines”
below for important information on SDM
replacement in both deployment and
non–deployment crashes.
Inspect SRS coil assembly wiring and steering wheel for
any sign of scorching, melting, or damage due to
excessive heat. If coil assembly wire or steering wheel is
damaged, replace them. The steering column and wheel
must be dimensionally checked to determine if they are
damaged. Refer to steering wheel of in this manual.
Never use SRS parts from another vehicle. This does not
include remanufactured parts purchased from an
authorized Isuzu Retailer; they may be used for SRS
repairs.
Do not attempt to repair the SDM, the SRS harness, the
SRS coil assembly, the air bag assembly, the steering
wheel, or the steering column. Service of these items is
replacement only. Verify replacement part numbers.
CAUTION: Proper operation of the SDM and
supplemental restraint system (SRS) requires that
any repairs to the vehicle structure return it to its
original production configuration.
SRS Connectors
CAUTION:The special yellow color connectors are
used for supplemental restraint system air bag circuit.
When removing the oable harnese, do not pull the cables
otherwile, cable disconnection may occur. When connect
the SRS connector, insert the connector completely.
Imperfect locking may cause malfunction of SRS circuit.
Removal
To remove the connector, hold the cover insulator (1) and
pull it. The cover insulator slides and lock will be released.
Do not hold the socket insulator (2).
827RW028

SUPPLEMENTAL RESTRAINT SYSTEM9J–33
Sensing And Diagnostic Module (SDM)
Service Precautions
WARNING: DURING SERVICE PROCEDURES, BE
VERY CAREFUL WHEN HANDLING SDM. NEVER
STRIKE OR JAR SDM. UNDER SOME
CIRCUMSTANCES, IT COULD CAUSE
DEPLOYMENT AND RESULT IN PERSONAL INJURY
OR IMPROPER OPERATION OF THE
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) . SDM
MOUNTING BRACKET BOLTS MUST BE
CAREFULLY TORQUED TO ASSURE PROPER
OPERATION. NEVER POWER UP THE SRS WHEN
SDM IS NOT RIGIDLY ATTACHED TO THE VEHICLE.
THE SDM COULD BE ACTIVATED WHEN POWERED
WHILE NOT RIGIDLY ATTACHED TO THE VEHICLE
WHICH COULD CAUSE DEPLOYMENT AND RESULT
IN PERSONAL INJURY.
WARNING: PROPER OPERATION OF THE SENSING
AND DIAGNOSTIC MODULE (SDM) REQUIRES THE
SDM TO BE RIGIDLY ATTACHED TO THE VEHICLE
STRUCTURE AND THAT THE ARROW ON THE
SENSOR BE POINTING TOWARD THE FRONT OF
THE VEHICLE.
SDM is specifically calibrated and is keyed to the SDM
location SRS wiring harness. Caution should be used to
ensure proper location of the SDM. The keying of the
SDM to its location and wiring harness connectors should
never be modified in the field.
Removal
1. Disable the SRS (Refer to “Disabling the SRS” in this
section).
2. Remove the transmission knob (for M/T) and transfer
lever knob.
3. Remove the front console assembly and disconnect
wiring harness connector.
4. Pull CPA (Connector Position Assurance) out and
push connector lock down to disconnect the SDM
harness connector.
5. Remove the three SDM fixing bolts and remove SDM.
827RW044
Legend
(1) SDM
(2) SRS Harness
(3) Connector Position Assurance
Installation
1. Install the SDM on bracket and fixing bolts and tighten
the fixing bolts to the specified torque.
Torque: 10 Nꞏm (1.0 Kgꞏm/87 Ib in)
2. Connect the SDM harness connector and after that,
put CPA into connector.
3. Install the front console.
4. Install the transmission knob (for M/T) and transfer
lever knob.

SUPPLEMENTAL RESTRAINT SYSTEM 9J–36
Installation
1. Connect air bag to wiring harness connector.
NOTE: Pass the lead wire through the tabs on the plastic
cover (wire protector) of air bag to prevent lead wire from
being pinched.
827RT009
2. Install air bag into steering wheel and tighten bolts to
specified sequence as shown in figure.
Torque: 8.8 Nꞏm (0.9 Kgꞏm/78 Ib in)
CAUTION: Never use the air bag assembly from
another vehicle. Use only new air bag assembly
proper to the Trooper which is being repaired.
827RT008
3. Enable the SRS (Refer to “Enabling the SRS” in this
section).

SUPPLEMENTAL RESTRAINT SYSTEM 9J–38
6. Apply a setting mark across the steering wheel and
shaft so parts can be reassembled in their original
position.
430RS004
7. Move the tires to the straight ahead position before
removing the steering wheel. Install steering wheel
puller onto steering wheel and remove steering wheel
with 5–8521–0016–0.
430RT009
8. Feed wiring through the wheel and remove wheel.
CAUTION: Never apply force to the steering wheel
in direction of the shaft by using a hammer or other
impact tools in an attempt to remove the steering
wheel. The steering shaft is designed as an energy
absorbing unit.
Installation
1. Install the steering wheel and align the setting marks.
430RS004
2. Tighten the steering wheel fixing nut to the specified
torque.
Torque : 34 Nꞏm (3.5 Kgꞏm/25 Ib ft)
3. Connect horn lead.
4. Connect air bag to wiring harness connector.
NOTE: Pass the lead wire through the tabs on the plastic
cover (wire protector) of air bag to prevent lead wire from
being pinched.
827RT009

SUPPLEMENTAL RESTRAINT SYSTEM 9J–40
3. Disconnect the yellow 2–pin connector located
behind the air bag assembly and remove air bag
assembly.Refer to “SRS Connectors” in this section
for removal and installation.
4. Disconnect horn lead connector.
827RT009
5. Remove the steering wheel attachment nut.
6. Apply a setting mark across the steering wheel and
shaft so parts can be reassembled in their original
position.
430RS004
7. Move the tires to the straight ahead position before
removing the steering wheel and remove wheel with
5–8521–0016–0.
430RT009
8. Feed wiring though the wheel and remove wheel.
9. Remove the steering lower cover and engine hood
opening lever.
10. Remove the driver knee bolster assembly.
11. Remove the steering column cover.
12. Remove air conditioning lower duct.
13. Disconnect the 12–pin wiring harness connectors
located at the base of steering column.
CAUTION: Never apply force to the steering wheel
in the direction of the shaft by using a hammer or
other impact tools in an attempt to remove the
steering wheel. The steering shaft is designed as an
energy absorbing unit.
14. Remove the combination switch assembly with SRS
coil.