2004 ISUZU TF SERIES instrument cluster

SUPPLEMENTAL RESTRAINT SYSTEM 9A-5

System Description
The SRS consists of the SRS control unit, the driver
air bag assembly, the SRS coil assembly, the
passenger air bag assembly and the “AIR BAG”
warning lamp in the instrument cluster. The SRS
control unit, SRS coil assembly (driver side only),
driver air bag assembly, passenger air bag assembly
and connector wire make up the deployment loops.
The function of the deployment loops is to supply
current through air bag assembly, which will cause
deployment of the air bags in the event of a frontal
crash of sufficient force, up to 30 degrees off the
centerline of the vehicle. The air bag assemblies are

only supplied enough current to deploy when the SRS
control unit detects vehicle velocity changes severe
enough to warrant deployment.
The SRS control unit contains a sensing device which
converts vehicle velocity change to an electrical signal.
The electrical signal generated is processed by the
SRS control unit and then compared to a value stored
in memory. When the generated signal exceeds the
stored value, the SRS control unit will cause current to
flow through the air bag assembly deploying the air
bags.



RTW49JLF000101

RESTRAINT CONTROL 9A1-13

Chart B “AIR BAG” warning lamp comes “ON” Steady

Step Action Yes No
1

1. When measurements are requested in this chart use 5-8840-
0285-0 DVM with correct terminal adapter from 5-8840-
0385-0.

2. Ignition switch “OFF.”

3. Connect scan tool to data link connector, follow directions as
given in the scan tool instruction MANUAL.

4. Ignition switch “ON.”

5. Request SRS diagnostic trouble code display.
Dose scan tool indicate “No Data Received”? Go to Step 2 Go to Step 3
2

1. Ignition switch “OFF”.

2. Inspect SRS control unit harness connector connection to
SRS control unit.
Is it securely connected to the SRS control unit? Ignition switch
“OFF.”
Replace SRS
control unit.
Go to Step 5 Connect SRS
control unit
securely to de–
activate shorting
clip in SRS control
unit harness
connector.
Go to Step 5
3 Using scan tool, request SRS data list.
Is “ignition” more than 9 volts? Go to Step 4 Ignition switch
“OFF.”
Replace SRS
control unit.
Go to Step 5
4

1. Ignition switch “OFF.”

2. Disconnect SRS coil and passenger air bag assemblies.
yellow connector located at base of steering column and
behind the glove box assembly.
Disconnect SRS control unit.

3. Disconnect the connector of “SRS Warning Lamp” of
instrument cluster.

4. Measure resistance from SRS control unit harness connector
terminal “40” to ground.
Does 5-8840-0285-0 DVM display “OL” (Infinite)? Go to Chart A Replace SRS
harness.
Go to Step 5
5 Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished? Repeat the “SRS
Diagnostic System
Check” Go to Step 5

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.

RESTRAINT CONTROL 9A1-15

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

Step Action Yes No
1

1. When measurements are requested in this chart, use 5-8840-
0285-0 DVM with correct terminal adapter from 5-8840-
0385-0.

2. Ignition switch “OFF.”
3. Remove and inspect “METER” fuse to the “AIR BAG”
warning lamp.
Is fuse good? Go to Step 2 Go to Step 7
2

1. Ignition switch “OFF.”

2. Disconnect SRS coil and passenger air bag assemblies.
Yellow connector located at base of steering column and
behind the glove box assembly.

3. Disconnect SRS control unit.

4. Ignition switch “ON.”
5. Measure voltage on SRS control unit harness connector from
terminal “39” to terminal “40” (ground).
Is system voltage present on terminal “39”? Go to Step 4 Go to Step 3
3

1. Ignition switch “OFF.”

2. Remove instrument meter cluster.
3. Check for proper connection to instrument cluster at SRS
warning lamp circuit terminal.

4. If ok, then remove and inspect “AIR BAG” bulb.
Is bulb good? Go to Step 5 Replace bulb.
Go to Step 6
4

1. Ignition switch “OFF.”

2. Disconnect instrument meter cluster harness connector.
3. Ignition switch “ON.”

4. Measure voltage on SRS control unit harness connector from
terminal “39” to terminal “40” (ground).
Is voltage 1 volt or less? Go to Chart A Replace SRS
harness.
Go to Step 6
5

1. Install bulb.

2. Measure resistance from instrument meter cluster harness
connector SRS warning lamp circuit terminal to SRS control
unit harness connector terminal “7”.
Is resistance 5.0 ohms or less? Service instrument
meter cluster.
Install instrument
meter cluster.
Go to Step 6 Replace SRS
harness.
Go to Step 6
6 Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished? Repeat the “SRS
Diagnostic System
Check” Go to Step 6
7 Perform chart C.
Was this step finished? Go to Step 8 Go to Step 1
8

1. Replace “METER” fuse.

2. Ignition switch “ON” wait 10 Seconds then ignition switch “Off.
“
3. Remove and inspect “METER” fuse.
Is fuse good? Install “METER”
fuse.
Go to Step 10 Go to Step 9

BRAKE CONTROL SYSTEM 5A-43

No ABS Warning Lamp

Step Action
Value(s) Yes No
1 Check the meter fuse for the instrument cluster
ignition feed circuit.
Is the fuse OK? - Go to Step 3 Go to Step 2
2 Replace the fuse.
Is the action complete? - Verify repair
Go to Step 3 -
3 1. Ignition “OFF,” disconnect the EHCU.
2. Ignition “ON,”engine “OFF.”
3. Observe the ABS warning lamp.
Is the ABS warning lamp “ON”?
- Go to Step 5 Go to Step 4
4 Repair or replace the meter circuit or meter.
Is the action complete? - Verify repair -
5 1. Check the EHCU circuit for an open, short to
ground, or short to voltage. Also, check the EHCU
ignition feed circuit for an open or short to ground
and the EHCU ground circuit for an open.
2. If a problem is found, repair as necessary.
Was a problem found?
- Verify repair Go to Step 6
6 1. Ignition “OFF,” reconnect the EHCU.
2. Ignition “ON,”engine “OFF.”
3. Observe the ABS warning lamp.
Is the ABS warning lamp “ON”?
- Verify repair Go to Step 7
7 Replace EHCU.
Note : Check the EHCU type for specification, the
EHCU is replaced.
(Specification; 2WD or 4WD Model)
Is the action complete? - Verify repair -

5D-2 PARKING BRAKE SYSTEM

Parking Brake Lever
Parking Brake Lever Assembly and Associated Parts (Bench Seat)



This illustration is based on RHD model.
740R300010

Legend

(1)
Front Console Assembly

(2)
Glove Box

(3)
Instrument Panel Driver Lower Cover Assembly

(4)
Driver Knee Bolster Assembly

(5)
Driver Air Bag


(6)
Steering Wheel/Steering Cowl

(7)
Meter Cluster Assembly

(8)
Dash Side Trim Cover

(9)
Front Piller Trim Cover

(10)
Instrument Panel Assembly & Cross Beam

10-28 CAB
INSTRUMENT PANEL
REMOVAL


This illustration is based on RHD model
RTW4A0LF001001

Disassembly Steps

1. Front console assembly

2. Glove box

3. Instrument panel driver lower cover
assembly

4. Driver knee bolster assembly

5. Driver air bag

6. Steering wheel/ steering cowl

7. Meter cluster assembly
8. Dash side trim cover
9. Front pillar trim cover
10. Front cover
11. Side cover

12. Instrument panel & Cross beam
assembly


13. Ashtray case

14. Center cluster assembly

15. Control lever assembly
16. Storage box assembly

17. Ashtray bracket
18. Meter assembly
19. Passenger lower bracket
20. Glove box cover

21. Passenger air bag (if so equipped)

22. Side ventilation grille

23. Vent duct assembly/Defroster nozzle
assembly
24. Instrument harness assembly

25. Instrument panel

26. Cross beam

CAB 10-29

Important Operations
1. Front Console Assembly


Refer to Floor Consol in this section.



2. Glove Box


Remove 2 fixing screws and pulling the handle.



3. Instrument Panel Driver Lower Cover Assembly
1) Remove the engine hood opener 2 fixing screws.
2) Remove the lower cover one fixing screw.
3) Pull out the cover (Stick type parking brake only).
4) Pull out the lower cover assembly.




4. Driver Knee Bolster Assembly


Remove 4 fixing bolts.
Caution:
For precaution on installation or removal of SRS-air bag
system, refer to section 9 “Supplemental Restraint System
(SRS) - AIR BAG”

5. Driver Air Bag
6. Steering Wheel/Steering Cowl


Refer to Section 3B “STEERING COLUMN” for steering
lock assembly removal steps.




7. Meter Cluster Assembly


Pull out the 4 clip positions.