wiring ISUZU TF SERIES 2004 User Guide

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-30 SUPPLEMENTAL RESTRAINT SYSTEM

SRS Control Unit
5. Remove the three SRS control unit fixing bolts and
remove SRS control unit.


RTW49JSH000101
Legent
(1) SRS control unit
(2) SRS Harness
(3) Connector Position Assurance

Service Precautions
WARNING: DURING SERVICE PROCEDURES, BE
VERY CAREFUL WHEN HANDLING SRS control
unit. NEVER STRIKE OR JAR SRS control unit.
UNDER SOME CIRCUMSTANCES, IT COULD
CAUSE DEPLOYMENT AND RESULT IN
PERSONAL INJURY OR IMPROPER OPERATION
OF THE SUPPLEMENTAL RESTRAINT SYSTEM
(SRS) . SRS control unit MOUNTING BRACKET
BOLTS MUST BE CAREFULLY TORQUED TO
ASSURE PROPER OPERATION. NEVER POWE
R
UP THE SRS WHEN SRS control unit IS NOT
RIGIDLY ATTACHED TO THE VEHICLE. THE SRS
control unit 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 SRS
CONTROL UNIT REQUIRES THE SRS CONTROL
UNIT TO BE RIGIDLY ATTACHED TO THE
VEHICLE STRUCTURE AND THAT THE ARROW
ON THE SENSOR BE POINTING TOWARD THE
FRONT OF THE VEHICLE.
SRS control unit is specifically calibrated and is keyed
to the SRS control unit location SRS wiring harness.
Caution should be used to ensure proper location of
the SRS control unit. The keying of the SRS control
unit 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 SRS
control unit harness connector.

Installation
1. Install the SRS control unit on bracket and fixing
bolts and tighten the fixing bolts to the specified
torque.
Torque: 7




2 N
 m (0.7




0.2 kg
 m/61 lb in)
2. Connect the SRS control unit harness connecto
r
and after that, put CPA into connector.
3. Install the front console.
4. Install the transmission knob (for M/T) and transfe
r
lever knob.

SUPPLEMENTAL RESTRAINT SYSTEM 9A-35

Steering Wheel
Service Precautions
WARNING: SAFETY PRECAUTIONS MUST BE
FOLLOWED WHEN HANDLING A DEPLOYED AI
R
BAG ASSEMBLY. AFTER DEPLOYMENT, THE AIR
BAG ASSEMBLY SURFACE MAY CONTAIN A
SMALL AMOUNT OF SODIUM HYDROXIDE, A BY–
PRODUCT OF THE DEPLOYMENT REACTION,
THAT IS IRRITATING TO THE SKIN AND EYES.
MOST OF THE POWER ON THE AIR BAG
ASSEMBLY IS HARMLESS. AS A PRECAUTION,
WEAR GLOVES AND SAFETY GLASSES WHEN
HANDLING A DEPLOYED AIR BAG ASSEMBLY,
AND WASH YOUR HANDS WITH MILD SOAP AND
WATER AFTERWARDS.
WARNING: WHEN CARRYING A LIVE AIR BAG
ASSEMBLY, MAKE SURE THE BAG AND TRIM
COVER ARE POINTED AWAY FROM YOU. NEVE
R
CARRY AIR BAG ASSEMBLY BY THE WIRES O
R
CONNECTOR ON THE UNDERSIDE OF MODULE.
IN THE CASE OF AN ACCIDENTAL DEPLOYMENT,
THE BAG WILL THEN DEPLOY WITH MINIMAL
CHANCE OF INJURY. WHEN PLACING ALIVE AI
R
BAG ASSEMBLY ON A BENCH OR OTHER
SURFACE, ALWAYS FACE BAG AND RIM COVER
UP, AWAY FROM THE SURFACE. NEVER REST A
STEERING COLUMN ASSEMBLY ON THE
STEERING WHEEL WITH THE AIR BAG
ASSEMBLY FACE DOWN AND COLUMN
VERTICAL. THIS IS NECESSARY SO THAT A FREE
SPACE IS PROVIDED TO ALLOW THE AIR BAG
ASSEMBLY TO EXPAND IN THE UNLIKELY EVENT
OF ACCIDENTAL DEPLOYMENT. OTHERWISE,
PERSONAL INJURY COULD RESULT.
In the event deployment has occurred, inspect coil
assembly wire for any signs of scorching, melting o
r
any other damage due to excessive heat. If the coil
has been damaged, replace it.

Removal
1. Remove the SRS air bag assembly. (Refer to
“Driver Air Bag Assembly” in this section)

2. Remove steering wheel attachment nut.

060R300009
3. Apply a setting mark across the steering wheel
and shaft so parts can be reassembled in thei
r
original position.
060R300024
4. 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.
5. 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 o
r
other impact tools in an attempt to remove the
steering wheel. The steering shaft is designed as
an energy absorbing unit.

SUPPLEMENTAL RESTRAINT SYSTEM 9A-37

SRS Coil Assembly
Service Precautions
WARNING: SAFETY PRECAUTIONS MUST BE
FOLLOWED WHEN HANDLING A DEPLOYED AI
R
BAG ASSEMBLY. AFTER DEPLOYMENT, THE AIR
BAG ASSEMBLY SURFACE MAY CONTAIN A
SMALL AMOUNT OF SODIUM HYDROXIDE, A BY–
PRODUCT OF THE DEPLOYMENT REACTION,
THAT IS IRRITATING TO THE SKIN AND EYES.
MOST OF THE POWER ON THE AIR BAG
ASSEMBLY IS HARMLESS. AS A PRECAUTION,
WEAR GLOVES AND SAFETY GLASSES WHEN
HANDLING A DEPLOYED AIR BAG ASSEMBLY,
AND WASH YOUR HANDS WITH MILD SOAP AND
WATER AFTERWARDS.
WARNING: WHEN CARRYING A LIVE AIR BAG
ASSEMBLY, MAKE SURE THE BAG AND TRIM
COVER ARE POINTED AWAY FROM YOU. NEVE
R
CARRY AIR BAG ASSEMBLY BY THE WIRES OR
CONNECTOR ON THE UNDERSIDE OF MODULE.
IN THE CASE OF AN ACCIDENTAL DEPLOYMENT,
THE BAG WILL THEN DEPLOY WITH MINIMAL
CHANCE OF INJURY. WHEN PLACING ALIVE AI
R
BAG ASSEMBLY ON A BENCH OR OTHER
SURFACE, ALWAYS FACE BAG AND RIM COVER
UP, AWAY FROM THE SURFACE. NEVER REST A
STEERING COLUMN ASSEMBLY ON THE
STEERING WHEEL WITH THE AIR BAG
ASSEMBLY FACE DOWN AND COLUMN
VERTICAL. THIS IS NECESSARY SO THAT A FREE
SPACE IS PROVIDED TO ALLOW THE AIR BAG
ASSEMBLY TO EXPAND IN THE UNLIKELY EVENT
OF ACCIDENTAL DEPLOYMENT. OTHERWISE,
PERSONAL INJURY COULD RESULT.
NOTE: In the event deployment has occurred, inspec
t
coil assembly wire for any signs of scorching, melting
or any other damage due to excessive heat. If the coil
has been damaged, replace it.

Removal
1. Remove the SRS air bag assembly. (Refer to
“Driver Air Bag Assembly” in this seciton)


2. Remove the steering wheel attachment nut.

060R300009
3. Apply a setting mark across the steering wheel
and shaft so parts can be reassembled in thei
r
original position.
060R300024
4. Move the tires to the straight ahead position before
removing the steering wheel and remove wheel
with 5-8521-0016-0.
5. Feed wiring though the wheel and remove wheel.
6. Remove the steering lower cover and engine hood
opening lever.
7. Remove the driver knee bolster assembly.
8. Remove the steering column cover.
9. Remove air conditioning lower duct.
10.Disconnect the wiring harness connectors located
at the base of steering column.

9A-38 SUPPLEMENTAL RESTRAINT SYSTEM

CAUTION: Never apply force to the steering wheel
in the direction of the shaft by using a hammer o
r
other impact tools in an attempt to remove the
steering wheel. The steering shaft is designed as
an energy absorbing unit.
11. Remove the combination switch assembly with
SRS coil.
NOTE: SRS coil is a part of combination switch
assembly, which cannot be replaced separately.
Therefore, be sure not to remove the SRS coil from
the combination switch assembly.

Installation
1. Install the combination switch assembly with SRS
coil.
2. Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark.
CAUTION: When turning the SRS coil
counterclockwise to full, stop turning if resistance
is felt. Forced further turning may damage the
cable in the SRS coil.
826RW014
Legend
(1) Neutral mark

3. Connect the wiring harness connectors located at
the base of steering column.
4. Install the air conditioning lower duct.
5. Install the steering column cover.
CAUTION: When installing the steering column
cover, be sure to wire (through each harness) as
illustrated so that the harness starter switch,
combination switch and SRS coil may not catch
wiring.
825RS048
6. Install the driver knee bolster assembly.
7. Install the steering lower cover and engine hood
opening lever.
8. Install the steering wheel and align the setting
marks.
060R300024

9A-40 SUPPLEMENTAL RESTRAINT SYSTEM

Steering Column
Service Precautions
WARNING: SAFETY PRECAUTIONS MUST BE
FOLLOWED WHEN HANDLING A DEPLOYED AI
R
BAG ASSEMBLY. AFTER DEPLOYMENT, THE AIR
BAG ASSEMBLY SURFACE MAY CONTAIN A
SMALL AMOUNT OF SODIUM HYDROXIDE, A BY–
PRODUCT OF THE DEPLOYMENT REACTION,
THAT IS IRRITATING TO THE SKIN AND EYES.
MOST OF THE POWER ON THE AIR BAG
ASSEMBLY IS HARMLESS. AS A PRECAUTION,
WEAR GLOVES AND SAFETY GLASSES WHEN
HANDLING A DEPLOYED AIR BAG ASSEMBLY,
AND WASH YOUR HANDS WITH MILD SOAP AND
WATER AFTERWARDS.
WARNING: WHEN CARRYING A LIVE AIR BAG
ASSEMBLY, MAKE SURE THE BAG AND TRIM
COVER ARE POINTED AWAY FROM YOU. NEVE
R
CARRY AIR BAG ASSEMBLY BY THE WIRES OR
CONNECTOR ON THE UNDERSIDE OF MODULE.
IN THE CASE OF AN ACCIDENTAL DEPLOYMENT,
THE BAG WILL THEN DEPLOY WITH MINIMAL
CHANCE OF INJURY. WHEN PLACING ALIVE AI
R
BAG ASSEMBLY ON A BENCH OR OTHER
SURFACE, ALWAYS FACE BAG AND RIM COVER
UP, AWAY FROM THE SURFACE. NEVER REST A
STEERING COLUMN ASSEMBLY ON THE
STEERING WHEEL WITH THE AIR BAG
ASSEMBLY FACE DOWN AND COLUMN
VERTICAL. THIS IS NECESSARY SO THAT A FREE
SPACE IS PROVIDED TO ALLOW THE AIR BAG
ASSEMBLY TO EXPAND IN THE UNLIKELY EVENT
OF ACCIDENTAL DEPLOYMENT. OTHERWISE,
PERSONAL INJURY COULD RESULT.
In the event deployment has occurred, inspect coil
assembly wire for any signs of scorching, melting o
r
any other damage due to excessive heat. If the coil
has been damaged, replace it.

Removal
1. Remove the SRS air bag assembly. (Refer to
“Driver Air Bag Assembly” in this section)


2. Remove the steering wheel attachment nut.

060R300009
3. Apply a setting mark across the steering wheel
and shaft so parts can be reassembled in thei
r
original position.
060R300024
4. Move the tires to the straight ahead position before
removing the steering wheel and removing wheel
with 5-8521-0016-0.
5. Feed wiring though the wheel and remove wheel.
6. Remove the steering lower cover and engine hood
opening lever.

SUPPLEMENTAL RESTRAINT SYSTEM 9A-41

7. Remove the driver knee bolster assembly.


RTW49JSH000401
Legend
(1) RHD
(2) LHD

8. Remove the steering column cover.
9. Disconnect the wiring harness connectors located
at the base of steering column.
CAUTION: Never apply force to the steering wheel
in direction of the shaft by using a hammer o
r
other impact tools in an attempt to remove the
steering wheel. The steering shaft is designed as
an energy absorbing unit.
10. Remove the combination switch assembly with
SRS coil.
SRS coil is a part of combination switch assembly,
which cannot be replaced separately. Therefore, be
sure not to remove the SRS coil from the combination
switch assembly.
11.Remove the snap ring.
12. Remove the cushion rubber.
13. Disconnect shift lock cable (A/T only).
14.Disconnect the starter switch harness connecto
r
located base of steering column.
15. Remove steering lock cylinder assembly.



16.Apply a setting mark across the universal joint and
steering shaft to reassemble the parts in thei
r
original position.
060R300038
17.Remove steering column assembly.

Installation
1. Install the steering column assembly and align the
setting marks on the universal joint and steering
shaft made during removal.
060R300038
2. Tighten the steering column fixing bolts (dash
panel side) to the specified torque.
Torque: 20 N




m (2.0 kg




m/14 lb ft)
3. Tighten the steering column fixing bolts (Pedal
bracket) to the specified torque.
Torque: 20 N





m (2.0 kg





m/14 lb ft)

9A-42 SUPPLEMENTAL RESTRAINT SYSTEM

4. Tighten the universal joint to the specified torque.
Torque: 31 N




m (3.2 kg




m/23 lb ft)
5. Install steering lock cylinder assembly.
6. Connect shift lock cable (For A/T)
7. Install cushion rubber.
8. Install snap ring.
9. Install the combination switch assembly with SRS
coil.
10. Connect the wiring harness connector located on
the base of steering column.
11. Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark.
CAUTION: When turning the SRS coil
counterclockwise to full, stop turning if resistance
is felt. Forced further turning may damage to the
cable in the SRS coil.
826RW014
Legend
(1) Neutral mark

12.Install steering column cover.
CAUTION: When installing the steering column
cover, be sure to wire (through each harness) as
illustrated so that the harness starter switch,
combination switch and SRS coil may not catch
wiring.


825RS048
13.Install the steering wheel and align the setting
marks.

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.

9A-48 SUPPLEMENTAL RESTRAINT SYSTEM

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
901RS146
The 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 when connected to
the passenger air bag 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 load tool should be used only when
specifically called for in the diagnostic procedures.

5-8840-0285-0 DVM
901RS163
The 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
901RW176