belt ISUZU TF SERIES 2004 Workshop Manual

SUPPLEMENTAL RESTRAINT SYSTEM 9A-1

RESTRAINTS
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
SERVICING
PAGE
Service Precaution ............................................................................................................ 9A- 3
General Description ...................................................................................................... 9A- 4
Restraint Devices ..................................................................................................... 9A- 4
System Description .................................................................................................. 9A- 5
SRS Component And Wiring Location View ............................................................... 9A- 6
Component Description ............................................................................................... 9A- 8
SRS Control Unit ...................................................................................................... 9A- 8
"Air Bag" Warning Lamp.......................................................................................... 9A- 8
SRS Coil Assembly................................................................................................... 9A- 9
Air Bag Assemblies .................................................................................................. 9A- 9
Seat Belt with Pretensioner (If so equipped) ......................................................... 9A- 10
Steering Column ....................................................................................................... 9A- 10
Knee Bolster ............................................................................................................. 9A- 10
Definitions...................................................................................................................... 9A- 10
Diagnosis .......................................................................................................................9A- 12
Diagnostic Trouble Codes ....................................................................................... 9A- 12
Scan Tool Diagnostics ............................................................................................. 9A- 12
Use Of Special Tools ................................................................................................ 9A- 12
SRS Connector Body Face Views................................................................................ 9A- 13
Repairs And Inspections Required After An Accident ............................................... 9A- 14
Accident With Deployment-Component Replacement And Inspections ............. 9A- 14
Accident With or Without Deployment-Component Inspection ........................... 9A- 14
SRS Control Unit Replacement Guidelines ............................................................ 9A- 14
Wiring Damage ......................................................................................................... 9A- 14
SRS Connector (Plastic Body And Terminal Metal Pin) Damage ......................... 9A- 14
SRS Wire Pigtail Damage......................................................................................... 9A- 14

SUPPLEMENTAL RESTRAINT SYSTEM 9A-3

PAGE
Steering Wheel ................................................................................................................... 9A- 35
Service Precautions ...................................................................................................... 9A- 35
Removal .........................................................................................................................9A- 35
Installation ..................................................................................................................... 9A- 36
SRS Coil Assembly ............................................................................................................ 9A- 37
Service Precautions ...................................................................................................... 9A- 37
Removal. ........................................................................................................................9A- 37
Installation. .................................................................................................................... 9A- 38
Steering Column ................................................................................................................9A- 40
Service Precautions ...................................................................................................... 9A- 40
Removal .........................................................................................................................9A- 40
Installation ..................................................................................................................... 9A- 41
Passenger Air Bag Assembly ........................................................................................... 9A- 44
Service Precautions ...................................................................................................... 9A- 44
Removal .........................................................................................................................9A- 44
Installation ..................................................................................................................... 9A- 45
Pretensioner Seat Belt (If so quipped) ............................................................................. 9A- 46
Removal .........................................................................................................................9A- 46
Installation ..................................................................................................................... 9A- 46
Main Data and Specifications ........................................................................................... 9A- 47
Fastener Tightening Specification............................................................................... 9A- 47
Special Tools...................................................................................................................... 9A- 48
5-8840-2421-0 SRS Driver/Passenger Load Tool........................................................ 9A- 48
5-8840-0285-0 DVM........................................................................................................ 9A- 48
Scan Tool .......................................................................................................................9A- 48
5-8840-0385-0 Connector Test Adapter Kit ................................................................. 9A- 49
5-8840-2468-0 SRS Deployment Tool .......................................................................... 9A- 49
5-8840-2420-0 SRS Deployment Fixture ...................................................................... 9A- 49
5-8840-2796-0 SRS Adapter for Load Tool .................................................................. 9A- 49
5-8840-2795-0 SRS Adapter for Deployment Tool ...................................................... 9A- 50
5-8521-0016-0 Steering Wheel remover ...................................................................... 9A- 50

9A-4 SUPPLEMENTAL RESTRAINT SYSTEM

Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE
TO FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS
SYSTEM REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners
or fastener joint interfaces. Generally, such
coatings adversely affect the fastener torque and
the joint clamping force, and may damage the
fastener. When you install fasteners, use the
correct tightening sequence and specifications.
Following these instructions can help you avoid
damage to parts and systems.
General Description
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 fo
r
that application. If the correct part numbe
r
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.


Restraint Devices
827RW006
Legent
(1) Deployed Air Bag
(2) Knee Bolster
(3) Seat Belt


The Supplemental Restraint System (SRS) helps
supplement the protection offered by the driver and
front passenger seat belts by deploying an air bag
from the center of the steering wheel and from the
front of the passenger side of the instrument panel.
The air bag deploys when the vehicle is involved in a
frontal crash of sufficient force up to 30 degrees off the
centerline of the vehicle. To further absorb the crash
energy there is a knee bolster located beneath the
instrument panel for both the driver and passenger,
and the steering column is collapsible.

827RW005

9A-10 SUPPLEMENTAL RESTRAINT SYSTEM

060R300013

Seat Belt with Pretensioner (If so
equipped)
The seat belt comprises a seat belt and a cylinder (a
cylinder filled with powder and an ignition device). In
cases of frontal collision which cause a shock
exceeding a specified level, the controller lets current
flow to the inflation circuit. The current ignites the
cylinder of the seat belt, producing gas. The gas helps
tighten the seat belt to restrain firmly the driver’s upper
half in his seat.




RTW49JSH000201







Steering Column
The steering column absorbs energy and is designed
to compress in a frontal crash to decrease the chance
of injury to the driver.
060R300038

Knee Bolster
The knee bolsters are used to absorb energy to
protect knees and control the forward movement of
the vehicle's front seat occupants during a frontal
crash, by limiting leg movement.

Definitions
Air Bag
An inflatable cloth cushion designed to deploy in
certain frontal crashes. It supplements the protection
offered by the seat belts by distributing the impact load
more evenly over the vehicle occupant's head and
torso.
Asynchronous
Performed in a nonperiodic fashion, (i.e., no defined
time or interval).
B+
Battery voltage, (B+) The voltage available at the
battery at the time of the indicated measurement.
With the key “ON” and the engine not running, the
system voltage will likely be between 12 and 12.5
volts. At idle, the voltage may be 14 to 16 volts. The
voltage could be as low as 10 volts during engine
cranking.
Bulb Check
The SRS control unit will cause the “AIR BAG” warning
lamp to flash seven times and then go “OFF”
whenever the ignition switch transitions to the ON
position from any other ignition switch position and no
malfunctions are detected.

SUPPLEMENTAL RESTRAINT SYSTEM 9A-13

SRS Connector Body Face Views

RTW49JMF000201
Legend
(1) SRS control unit
(2) Driver Air Bag Assembly
(3) Passenger Air Bag Assembly (4) “Air Bag” Warning Lamp
(5) DLC
(6) Pretensioner Seat Belt

9A-14 SUPPLEMENTAL RESTRAINT SYSTEM

Repairs And Inspections Required
After An Accident
If any SRS components are damaged, they must be
replaced. If SRS component mounting points are
damaged, they must be replaced.
 Never use SRS parts from another vehicle. This
does not include remanufactured parts purchased
from an authorized dealer; they may be used fo
r
SRS repairs.
 Do not attempt to service the SRS control unit, the
SRS coil assembly, or the air bag assembly.
Service of these items is by replacement only.

Verify the part number of replacement air bag
assembly.

CAUTION: Never use the air bag assembly from
another vehicle and difference model year air bag
assembly.
Use only new air bag assembly proper to the
TFR/S which is being repaired.
CAUTION: Proper operation of the sensors and
supplemental restraint system (SRS) requires that
any repairs to the vehicle structure return it to the
original production configuration. Deployment
requires, at a minimum, replacement of the SRS
control unit, air bag assembly and dimensional
inspection of the steering column. Any visible
damage to the SRS control unit mounting bracket
(s) requires replacement, and the steering column
must be dimensionally inspected, whethe
r
deployment occurred or not.
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
 SRS control unit

CAUTION: Refer to “SRS control unit
Replacement Guidelines” below for important
information on SRS control unit replacement in
both deployment and non deployment crashes.
 SRS coil assembly — Inspect wiring and connecto
r
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 fo
r
any distortion, bending, cracking, or other damage.
 I/P steering column reinforcement plate —Inspect
for any distortion, bending, cracking, or othe
r
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.

SRS Control Unit Replacement Guidelines
SRS control unit replacement policy requires
replacement of SRS control unit, after crash involving
air bag deployment when “SRS Warning Lamp” turn
“ON”, “SRS Diagnosis” should be done according to
Section “Restraint Control System.”

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.

9A-28 SUPPLEMENTAL RESTRAINT SYSTEM

– Driver air bag assembly
– Passenger air bag assembly
– Steering wheel
– SRS coil assembly
– Steering column
– Knee bolster and instrument panel mounting
attachments
– Driver seat and belt
– Passenger seat and belt
– SRS control unit
SRS control unit always should be checked according
to “SRS Control Unit Replacement Guidelines.”
CAUTION: Refer to “SRS control unit Replacement
Guidelines” below for important information on
SRS control unit 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 SRS control unit, 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 SRS control
unit 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 cable harness, do not
pull the cables otherwise, 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

9A-46 SUPPLEMENTAL RESTRAINT SYSTEM

Pretensioner Seat Belt (If so quipped)
Service Precaution
WARNING: WHEN PERFORMING SERVICE ON OR
AROUND THE PRETENSIONER SEAT BELT O
R
THE PRETENSIONER SEAT BELT WIRING,
FOLLOW THE PROCEDURES LISTED BELOW TO
TEMPORARILY DISABLE THE PRETENSIONE
R
SEAT BELT.
FAILURE TO FOLLOW PROCEDURES COULD
RESULT IN POSSIBLE THE PRETENSIONER SEAT
BELT DEPLOYMENT, PERSONAL INJURY O
R
OTHERWISE UNNEEDED THE PRETENSIONE
R
SEAT BELT REPAIR.
AS A PRECAUTION, WEAR GLOVES AND SAFETY
GLASSES WHEN PERFORMING THE
PRETENSIONER SEAT BELT. WHEN DEPLOY A
LIVE PRETENSIONER SEAT BELT AT OUTSIDE
THE VEHICLE, DEPLOYMENT HARNESS SHALL
REMAIN SHORTED AND NOT BE CONNECTED TO
A POWER SOURCE UNTIL THE PRETENSIONE
R
SEAT BELT IS TO BE DEPLOYED. THE
PRETENSIONER SEAT BELT WILL IMMEDIATELY
DEPLOY WHEN A POWER SOURCE IS
CONNECTED TO IT. CONNECTING THE
DEPLOYMENT HARNESS SHOULED ALWAYS BE
THE FINAL STEP IN THE PRETENSIONER SEAT
BELT DEPLOYMENT PROCEDURE. FAILURE TO
FOLLOW PROCEDURES IN THE ORDER LISTED
COULD RESULT IN PERSONAL INJURY.
Parts Location


RTW49JSH000301
Legend
(1) Seat
(2) Bolt
(3) Pretensioner Harness
(4) Pretensioner

Removal
1. Turn ignition switch to “LOCK”, remove key.
2. Remove the foot rest located behind the seat.
3. Remove the cover on seat slide.
4. Disconnect the pretensioner connector at the
base of the seat.
5. Remove four fixing bolts the seat slide and
remove seat.
6. Remove the seat cover.
7. Remove the pretensioner seat belt assembly.
Installation
1. Install the pretensioner seat belt assembly.
2. Install the seat cover.
3. Install the seat on seat slide and four fixing bolts.
4. Connect the yellow pretensioner connector at the
base of the seat.
5. Install the cover on seat slide.
6. Install the foot rest located behind the seat.

SUPPLEMENTAL RESTRAINT SYSTEM 9A-47

Main Data and Specifications
Fastener Tightening Specification
Application N




m kg




m Ft.lb
SRS control unit 7 0.7 5
Steering wheel fixing bolt 35 3.5 25
Steering column (dash panel side fixing bolts) 20 2.0 14
Steering column (Pedal bracket fixing bolt) 20 2.0 14
Steering column (Universal joint fixing bolt) 31 3.2 23
Passenger Air Bag fixing bolt & nut 8 0.8 5.8
Pretensioner seat belt bolt 55 5.6 40

RESTRAINT CONTROL 9A1-5

The SRS control unit displays the trouble codes by
flashing the warning lamp. Each code that is displayed
will consist of a number of flashes which represents the
tens digit, a 1.2 second pause, following by a number of
flashes which represents the ones digit of the code.
Each code is displayed one time before moving on to
the next code. After all of the codes have been
displayed, the entire code sequence will continually by
repeated until ground is removed from terminal 4 of the
DLC connector.


Two special codes exist when reading in the flash code
mode (Flash Code 12 and Flash Code 13). “Flash
Code 12” will always be the first code displayed when
the flash code mode is enable Code 12 is not an
indication of a SRS problem but an indication that the
flash code mode has been enabled. If there are no
active or history codes present, the SRS control unit will
display code 12 until ground is removed from the DLC
connector at terminal 4. “flash Code 13” will be
displayed if history codes are present. To read the
history codes a scan tool must be used.


060R300051
DATA LIST (Tech 2)









DISPLAY on Tech 2 UNIT VALUE
Driver Airbag Loop
Enabled/Disabled
Passenger Airbag Loop
Enabled/Disabled
System Voltage V 12.0
Driver Seat Belt Status
Not Backled/Backled