power ISUZU TF SERIES 2004 Owner's Manual

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

RESTRAINT CONTROL 9A1-3

Diagnostic Information
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.


Diagnostic Procedures
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 NON
POWERED, PROBE-TYPE TESTER.
INSTRUCTIONS IN THIS MANUAL MUST BE
FOLLOWED CAREFULLY, OTHERWISE PERSONAL
INJURY MAY RESULT.
The diagnostic procedures used in this section are
designed to aid in finding and repairing SRS problems.
Outlined below are the steps to find and repair SRS
problems quickly and effectively. Failure to carefully
follow these procedures may result in extended
diagnostic time, incorrect diagnosis and incorrect parts
replacement.
1. Perform The “SRS Diagnostic System Check”.
The “SRS Diagnostic System Check” should always
be the starting point of any SRS diagnostics. The
“SRS Diagnostic System Check” checks for prope
r
“AIR BAG” warning lamp operation and checks for
SRS trouble codes using both “Flash Code” and
“Scan Tool” Methods.
2. Refer To The Proper Diagnostic Chart As
Directed By The “SRS Diagnostic System
Check”.
The “SRS Diagnostic System Check” will lead you to
the correct chart to diagnose any SRS problems.
Bypassing these procedures may result in extended
diagnostic time, incorrect diagnosis and incorrect
parts replacement.

3. Repeat The “SRS Diagnostic System Check”
After Any Repair Or Diagnostic Procedures Have
Been Performed.
Preforming the “SRS Diagnostic System Check”
after all repair or diagnostic procedures will assure
that the repair has been made correctly and that no
other conditions exist.

Diagnostic Codes
The SRS control unit maintains a history record of all
diagnostic codes that have been detected since the
SRS codes were last cleared during service.
1. Active Codes - Faults that are presently detected this
ignition cycle. Active codes are stored in RAM
(Random Access Memory).
2. History Codes - All faults detected since the last time
the history fault memory was cleared. History codes
are stored in EEPROM. (Electronically Erasable
Programmable Read only Memory)

How To Read Trouble Codes
All codes (Active and history) can be read (or cleared)
by using a scan tool or equivalent.
If a PDT is not available, have the vehicle serviced by
HOLDEN dealer.

How To Clear Trouble Codes
Trouble codes can only be cleared by using a Scan
Tool. If a “scan tool” is not available then inform the
owner of the stored codes and suggest that the codes
are cleared upon the next visit to an Isuzu dealership.

Scan Tool Diagnostics
A scan tool can be used to read current and history
codes and to clear all history codes after a repair is
complete. The scan tool must be updated to
communicate with the SRS through a replaceable
cartridge or a manufacturer's update before it can be
used for SRS diagnostics. To use the scan tool,
connect it to the DLC connector and turn the ignition
switch “ON”. Then follow the manufacturer's directions
for communication with the SRS. The scan tool reads
serial data from the SRS control unitSRS control unit
“Serial Data” output (terminal 21) to the DLC connector
(terminal 2).

Basic Knowledge Required
Before using this section of the Service Manual, there is
some basic knowledge which will be required. Without
this knowledge, you will have trouble using the
diagnostic procedures in this section. Use care to
prevent harm or unwanted deployment. Read all

RESTRAINT CONTROL 9A1-11

3.
When all circuitry outside the SRS control unit has
been found to operate properly, as indicated by the
appropriate diagnostic chart, then and only then
should the SRS control unit be replaced.


Chart A SRS control unit Integrity Check
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SRS CONTROL
UNIT. NEVER STRIKE OR JAR THE SRS CONTROL UNIT. NEVER POWER UP THE SRS WHEN THE SRS
CONTROL UNIT IS NOT RIGIDLY ATTACHED TO THE VEHICLE. ALL SRS CONTROL UNIT AND MOUNTING
BRACKET FASTENERS MUST BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD
THE FRONT OF THE VEHICLE TO ENSURE PROPER OPERATION OF THE SRS. 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

Step Action Yes No
1

1. This chart assumes that the “SRS Diagnostic System
Check” and either a symptom chart or a diagnostic trouble
code chart diagnosis have been performed. When all
circuitry outside the SRS control unit has been found to
operate properly, as indicated by the appropriate diagnostic
chart, and the symptom or DTC remains current, the
following

2. Diagnostic procedures must be performed to verify the need
for SRS control unit replacement.

3. Ignition switch “OFF”.
4. Reconnect all SRS components, ensure all components are
properly mounted.

5. Ensure the ignition switch has been “OFF” for at least 15
seconds.

6. Note “AIR BAG” warning lamp as ignition switch is turned
“ON.”
Does warning lamp flash 7 times then go “OFF”? The symptom or
DTC is no longer
occurring.
Clear SRS
diagnostic trouble
codes.
Repeat “SRS
Diagnostic System
Check” Go to Step 2
2 Using a scan tool request diagnostic trouble code display.
Is the same symptom or DTC occurring as was when the “SRS
Diagnostic System Check” was first performed? Go to Step 3 Ignition switch
“OFF”.
Go to the
appropriate chart for
the indicated
malfunction.
3
1. Clear “SRS Diagnostic Trouble Codes”.

2. Ignition switch “OFF” for at least two minutes.

3. Note “AIR BAG” warning lamp as ignition switch is turned
“ON.”
Does warning lamp flash 7 times then go “OFF”? SRS is functional
and free of
malfunctions.
No further diagnosis
is required.
Go to Step 4 Ignition switch
“OFF”.
Replace SRS control
unit.
Go to Step 4
4 Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished? Repeat the “SRS
Diagnostic System
Check” Go to Step 4

9A1-14 RESTRAINT CONTROL SYSTEM

Chart C “AIR BAG” Warning Lamp Does Not Come “ON” Steady


RTW49JLF000101

Circuit Description
When the ignition switch is first turned “ON”, “Ignition 1”
voltage is applied from the “METER” fuse to the “AIR
BAG” warning lamp which is connected to “SRS
Warning Lamp”, terminal “39”. The “SRS” fuse appl
y
system voltage to the “Ignition 1” inputs, terminals “35”.
The SRS control unit responds by flashing the “AIR
BAG” warning lamp seven times. If “Ignition 1” is more
than 16 volts, the “AIR BAG” warning lamp will be still
“OFF” solid with no DTCs set.

Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
1.
This test decides whether power is available to SRS
control unit warning lamp power feed circuit.
2.
This test determines whether the voltage is present
in the warning lamp circuit.
3.
This test determines if the malfunction is in the
instrument cluster.
4.
This test checks for open in the warning lamp
circuitry.
5.
This test isolates the SRS warning lamp circuit and
checks for a short in the SRS warning lamp circuit to
B+.
8.
This test checks for a short from the SRS control
unit warning lamp power feed circuit to ground.
9.
This test determines whether the short to ground is
due to a short in the wiring.

9A1-38 RESTRAINT CONTROL SYSTEM

DTC B0051 (Flash Code 51) Squib Circuit Activated (Crash Deteted)
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SRS CONROL UNIT.
NEVER STRIKE OR JAR THE SRS CONTROL UNIT. NEVER POWER UP THE SRS WHEN THE SRS CONTROL
UNIT IS NOT RIGIDLY ATTACHED TO THE VEHICLE. ALL SRS CONTROL UNIT AND MOUNTING BRACKET
FASTENERS MUST BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD THE
FRONT OF THE VEHICLE TO ENSURE PROPER OPERATION OF THE SRS. THE SRS CONTROL UNIT CAUSE
DEPLOYMENT AND RESULT IN PERSONAL INJURY.


Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2. Go to the “SRS
Diagnostic System
Check”
2 Ignition switch “OFF.”
Have air bag assemblies deployed? Replace
components and
perform
inspections as
directed in
“repairs and
inspections
required after an
accident” in this
section.
clear diagnostic
trouble codes.
Repeat “SRS
Diagnostic System
Check” Go to Step 3
3 Inspect front of vehicle and undercarriage for sings of impact.
Were signs of impact found? Replace
components and
perform
inspections as
directed in
“Repairs and
Inspections
Required After An
Accident” in this
section.
Clear diagnostic
trouble codes.
Repeat “SRS
Diagnostic System
Check” Ignition switch
“OFF”.
Replace SRS
control unit.
Reconnect all SRS
system
components,
ensure all
components are
properly mounted.
Repeat “SRS
Diagnostic System
Check”

9A1-40 RESTRAINT CONTROL SYSTEM

DTC Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
2.
If air bag assembly have not deployed, DTC B0053
may have falsely set.
3.
If DTC B0053 has set with no signs of frontal impact,
the diagnostic trouble code has falsely set.


DTC B0053 (Flash Code 53) Deployment Command Despite Present Trouble Code
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SRS CONTROL
UNIT. NEVER STRIKE OR JAR THE SRS CONTROL UNIT. NEVER POWER UP THE SRS WHEN THE SRS
CONTROL UNIT IS NOT RIGIDLY ATTACHED TO THE VEHICLE. ALL SRS CONTROL UNIT AND MOUNTING
BRACKET FASTENERS MUST BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD
THE FRONT OF THE VEHICLE TO ENSURE PROPER OPERATION OF THE SRS. 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.


Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2 Go to the “SRS
Diagnostic System
Check”
2 Ignition switch “OFF.”
Have air bag assembles deployed? Replace
components and
perform
inspections as
directed in
“Repairs And
Inspections
Required After An
Accident” in this
section.
Clear diagnostic
trouble codes.
Repeat the “SRS
Diagnostic System
Check” Go to Step 3
3 Inspect front of vehicle and undercarriage for signs of impact.
Were signs of impact found? Replace
components and
perform
inspections as
directed in
“Repairs And
Inspections
Required After An
Accident” in this
section.
Clear diagnostic
trouble codes.
Repeat “SRS
Diagnostic System
Check” Ignition switch
“OFF.”
Replace SRS
control unit.
Reconnect all SRS
system
components,
ensure all
components are
properly mounted.
Repeat the “SRS
Diagnostic System
Check”

9A1-62 RESTRAINT CONTROL SYSTEM

DTC B1000 (Flash Code 72) SDM Internal Fault (SDM=SRS control unit)
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SRS CONTROL
UNIT. NEVER STRIKE OR JAR THE SRS CONTROL UNIT. NEVER POWER UP THE SRS WHEN THE SRS
CONTROL UNIT IS NOT RIGIDLY ATTACHED TO THE VEHICLE. ALL SRS CONTROL UNIT AND MOUNTING
BRACKET FASTENERS MUST BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD
THE FRONT OF THE VEHICLE TO ENSURE PROPER OPERATION OF THE SRS. 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.
CAUTION: If DTC B1000 can not clear by Tech2, it is necessary to replace the SRS control unit.

Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Ignition switch
“OFF.”
Replace SRS
control unit.
Repeat the “SRS
Diagnostic System
Check” Go to the “SRS
Diagnostic System
Check”

PROPELLER SHAFT 4A-9


Phasing
The propeller shaft is designer and built with the yoke lugs
(ears) in line with each other. This design produces the
smoothest running shaft possible, called phasing. Vibration can
be caused by an out-of-phase propeller shaft. The propeller
shaft down each time the universal joint goes around. This
vibration would be the same as a person snapping rope and
watching the “wave” reaction flow to the end. A propeller shaft
working in phase would be similar to two persons snapping a
rope at the same time, and watching the “waves” meet and
cancel each other out. In comparison, this would be the same
as the universal joints on a propeller shaft. A total cancellation
of vibration produces a smooth flow of power in the driveline. It
is very important to apply a reference mark to the propeller
shaft before removal, to assure installation alignment.


401RW015
Universal Joint
A universal joint consists of two Y-shaped yokes
connected by a crossmember called a spider.
The spider is shaped like a cross. Universal joints are
designed to handle the effects of various loadings and
front or rear axle windup during acceleration. Within the
designed angle variations, the universal joint will operate
efficiently and safely. When the design angle is changed
or exceeded the operational life of the joint may decrease.
The bearings used in universal joints are of the needle
roller type. The needle rollers are held in place on the
trunnions by round bearing cups. The bearing cups are
held inside the yokes by snap rings.

REAR AXLE 4B-7

REAR AXLE ASSEMBLY
General Description
A03R300001

The rear axle assembly is of the semi–floating type in
which the vehicle weight is carried on the axle
housing .
The center line of the pinion gear is below the center
line of the ring gear (hypoid drive).
All parts necessary to transmit power from the
propeller shaft to the rear wheels are enclosed in a
banjo type axle housing.
The 220 mm (8.6 in) ring gear rear axle uses a
conventional ring and pinion gear set to transmit the
driving force of the engine to the rear wheels. This
gear set transfers this driving force at a 90 degree
angle from the propeller shaft to the drive shafts.
The axle shafts are supported at the wheel end of the
shaft by a double tapered roller bearing.
The pinion gear is supported by two tapered roller
bearings. The pinion depth is set by a shim pack
located between the gear end of the pinion and the
roller bearing that is pressed onto the pinion. The
pinion bearing preload is set by crushing a collapsible
spacer between the bearings in the axle housing.
The ring gear is bolted onto the differential cage with
12 bolts.
The differential cage is supported in the axle housing
by two tapered roller bearings. The differential and ring
gear are located in relationship to the pinion by using
selective shims and spacers between the bearing and
the differential cage. To move the ring gear, shims are
deleted from one side and an equal amount are added
to the other side. These shims are also used to
preload the bearings which are pressed onto the
differential cage. Two bearing caps are used to hold
the differential into the rear axle housing.
The differential is used to allow the wheels to turn at
different rates of speed while the rear axle continues
to transmit the driving force. This prevents tire
scuffing when going around corners and prevents
premature wear on internal axle parts.
The rear axle is sealed with a pinion seal, a seal at
each axle shaft end, and by a liquid gasket between
the differential carrier and the axle housing

4B-18 REAR AXLE

17.
Install brake pipe and ABS sensor and tighten it to
the specified torque.

Torque :

ABS Sensor
8 N
m (0.8 kg
m/69 lb
ft)

Brake Pipe
16 N
m (1.6 kg
m/12 lb
ft)
420R30003

18.
Bleed brake pipe at the wheel cylinder. (Refer to
the section “Power-assisted Brake System”)
19.
Install brake drum.


Install propeller shaft. (Refer to Section “Rear
Propeller Shaft”.)


Refill differential oil.


Install wheel and tire.


Lower vehicle.