2004 ISUZU TF SERIES Lead

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 9A1-7

System Schematic


RTW49JLF000101

SRS Diagnostic System Check
The diagnostic procedures used in this section are
designed to find and repair SRS malfunctions. To get
the best results, it is important to use the diagnostic
charts and follow the sequence listed below:
A
Perform the “SRS Diagnostic System Check.”

The “SRS Diagnostic System Check” must be the
starting point of any SRS diagnostics. The “SRS
Diagnostic System Check” checks for proper “AIR
BAG” warning lamp operation, the ability of the SRS
control unit to communicate through the “Serial
Data” line and whether SRS diagnostic trouble codes
exist.

B
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 malfunctions.
Bypassing these procedures may result in extended
diagnostic time, incorrect diagnosis and incorrect
parts replacement.
C
Repeat the “SRS Diagnostic System Check” after
any repair or diagnostic procedures have been
preformed.

Performing the “SRS Diagnostic System Check”
after all repair or diagnostic procedures will ensure
that the repair has been made correctly and that no
other malfunctions exist

BRAKES 5C-9
MAIN DATA AND SPECIFICATIONS
FRONT DISC BRAKE mm(in.) 4

2 4

4, 4

2 HIGH RIDE
Caliper type Pin slide
Disc outside diameter 256(10.079) 280 (11.023)
Disc thickness 26(1.024) 27 (1.063)
Piston diameter 42.8 (1.685)

2 45.5 (1.79)
Adjustment method Self-adjusting
REAR DRUM BRAKE mm(in.) 4

2 4

4
Type Leading and Trailing
Drum inside diameter 254(10.008) 295 (11.614)
Brake lining dimension 244

50

5 283

45

5
(Length
Width
Thickness) (9.57
1.97
0.20) (11.14
1.77
0.20)
Adjustment method Self-adjusting
WHEEL CYLINDER mm(in.)
Inside diameter : rear 25.4 (1.000) 23.8 (0.937)
MASTER CYLINDER mm(in.)
Type Split
Bore diameter 25.4 (1.000)
Piston stroke (Primary + Secondary) 21.8 + 12 (0.86 + 0.47)
VACUUM SERVO mm(in.) 6VE1/C24NE 4JA1-T/4JA1-TC/4JH1-TC
Diaphragm diameter 205(8.077) + 230(9.055) 180(7.087) + 205(8.077)
4JA1-T
Power cylinder stroke 35 (1.378)
PEDAL RATIO 3.7
BALANCE EBD (with ABS)
Type Load sensing proportioning valve (without ABS)
Blend valve (without ABS)

BRAKES 5C-23

RTW35CSH001301

4) Failure on front master cylinder.
In case of failure on front master cylinder the pressure on
the inlet port (C) drop to zero. The pressure from inlet por
t
(A) acts on the bypass piston (2) and move it by comprising
of bypass spring (3). It makes possible the communication
between the inlet port (A) to outlet port (B) through the
bypass system. The outlet pressure (B) reaches the inle
t
pressure (A) and the LSPV is bypassed.


Valve Maintenance
In the case to fluid lead or other a abnormalities, faulty valve
should be replaced.
Note:
The load sensing proportioning valve is not repairable and
must be replaced as a completed assembly.


LOAD SENSING PROPORTIONING
VALVE (LSPV) ADJUSTMENT
RTW35CSH000301

1. Fluid Pressure Measurement
1) Rear axle weight adjustment
With an axle eight meter, adjust the rear axle weight with
a person sitting in the driver’s seat and a weight loaded
in the rear body.
N (kg/lb)

MODEL Adjustment value
4

2 7845 (800/1764)
4
2 HIGH RIDE
4

4 9316 (950/2095)

RTW35CSH000101





2) Installation of a fluid pressure gauge
Remove the air bleeder of the left hand wheel front and
rear brakes. Bleed air out of the fluid pressure gauge
with the measurement hose of the fluid pressure gauge
installed.
Pressure Tester: Brake oil (Fluid pressure gauge)
5-8840-2190-0

5C-44 BRAKES
REAR DRUM BRAKE ASSEMBLY
DISASSEMBLY

First, disassemble the brake drum. Then disassemble the rear brake assembly.
Refer to the “REAR AXLE ” section for the brake drum disassembly procedure.

RTW35CMF000201

MAJOR COMPONENTS
Disassembly Steps

1. Spring ; adjuster
2. Ring ; Adjuster lever
3. Lever ; adjuster

4. Spring ; Shoe hold
5. Pin ; Shoe hold

6. Spring ; Shoe to shoe, lower
7. Adjuster assembly
8. Spring ; shoe to shoe, upper
9. Shoe ; leading

10. Shoe ; trailing
11. Spring ; lever return
12. Retainer
13. Washer ; lever
14. Lever ; parking
15. Bolt ; wheel cylinder
16. Wheel cylinder assembly
17. Cover
18. Back plate

MINOR COMPONENTS
Disassembly Steps
Wheel Cylinder Assembly (14)

19. Piston
20. Cup
21. Boot ; piston

22. Return spring
23. Bleeder
24. Cap ; bleeder

BRAKES 5C-47
REASSEMBLY

RTW35CMF000301

MINOR COMPONENTS
Reassembly Steps
Wheel cylinder Assembly (7)

1. Piston assembly
2. Cup ; piston
3. Return spring



4. Boot ; piston

5. Bleeder
6. Cap ; bleeder

MAJOR COMPONENTS
Reassembly Steps

7. Back plate
8. Cover

9. Wheel cylinder assembly

10. Bolt ; wheel cylinder

11. Shoe ; leading

12. Lever ; parking

13. Washer ; lever

14. Retainer
15. Spring ; lever return



16. Shoe ; trailing

17. Spring ; shoe to shoe, upper

18. Adjust assembly
19. Spring ; shoe to shoe ; lower

20. Lever ; adjuster

21. Ring ; Adjuster lever
22. Spring ; shoe hold

23. Pin ; shoe hold

24. spring ; adjuster

BRAKES 5C-49
308R300008







11. Shoe ; leading

Be sure to use new spring; shoe hold.
12. Lever ; parking
13. Washer ; lever
14. Retainer
Install the lever, the washer and the retainer to the leading
brake shoe.



Apply grease to the sliding surfaces of the lever and
brake shoe.

Be sure to use new retainer and washer.
305R300009



















16. Shoe ; trailing


Be sure to use new spring; shoe hold.
17. Spring ; shoe to shoe, upper
18. Adjuster assembly
1. Apply grease to each of the parts shown in the
illustration before installing the brake shoe.

Lever; adjuster-shoe

Adjuster-shoe



2. Clean the adjuster bolt (5) and the adjuster rods (1) (4).
Apply grease to the threaded portion of the adjuster bolt.
3. Install the adjuster rod to the adjuster bolt.
4.
Apply grease to the adjuster asm ends (2) (3). Set the
spring ; upper to the adjuster asm, then install them to
the brake shoe.

305R300010











5. Before setting the brake shoes, apply grease to the back
plate portions (1) contacting the brake shoe edge as
shown in the illustration.
6.
Apply grease to the wheel cylinder parts contacting the
brake shoe (2).
7. Install the brake shoe.
Note :


Be careful not to damage the wheel cylinder dust cover.


Do not allow the wheel cylinder piston to fly free.

PARKING BRAKE SYSTEM 5D-1

SECTION 5D
BRAKES
PARKING BRAKE SYSTEM
CONTENTS

Service Precaution .......................................... 5D-1
Service Precaution ....................................... 5D-1
General Description ...................................... 5D-1
Parking Brake Lever ........................................ 5D-2
Parking Brake Lever Assembly and
Associated Parts (Bench Seat) .................. 5D-2
Removal ....................................................... 5D-3
Installation............................................................
5D-3
Front Parking Brake Cable....................................
5D-5
Front Parking Brake Cable and Associated
Parts (Bench Seat).........................................
5D-5
Removal...............................................................
5D-6
Installation............................................................
5D-6
Parking Brake Lever...............................................
5D-8
Parking Brake Lever Assembly and Associated
Parts (Buckle Seat)....................................... 5D-8
Removal ....................................................... 5D-8
Installation .................................................... 5D-8
Parking Brake Rear Cable ............................... 5D-9
Parking Brake Rear Cable and Associated
Parts ............................................................ 5D-9
Removal ....................................................... 5D-10
Installation .................................................... 5D-10
Inspection and Repair ................................... 5D-11
Parking Brake Adjustment ............................ 5D-11
Main Data and Specifications........................... 5D-12
Troubleshooting ............................................ 5D-13


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
Pulling up the parking brake lever by hand will set the
parking brake. By means of a ratchet type lock, the
lever can be held in that position until it is released. The
position of the lever is transmitted through cable/leve
r
systems to the rear wheels. These parts are designed
to obtain sufficient braking force even when parking on
slopes. When the parking brake is set, or when the
ignition SW is in the "ON" position, the brake warning
light illuminates. The rear wheel parking brake is a
leading-trailing brake (mechanical inside expansion
type) built in the rear drum brake. Parking brake
adjustment is made through the adjusting hole (bored
through back plate). Parking brake lever stroke should
be adjusted to 8

14 notches with 30kg (bench seat) o
r
6

8 notches with 30kg (bucket seat). Refer to “Parking
Brake Adjustment" in this section.