2004 ISUZU TF SERIES wiring

9A1-18 RESTRAINT CONTROL SYSTEM

DTC Will Clear When
The ignition switch is turned “OFF.”

DTC Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
2.
This test determines whether the malfunction is in
the SRS control unit.
3.
This test verifies connection of the yellow connector.
4.
This test cheeks for proper operation of the shorting
clip in the yellow connector.
5.
The test checks for a malfunction passenger air bag
assembly.
6.
This test determines whether the malfunctioning is
due to shortening in the wiring.
Diagnostic Aids
An intermittent condition is likely to be caused by a short
between circuits “Passenger Bag High” and “Passenger
Bag Low” or a malfunctioning shorting clip on the
passenger air bag assembly which would require
replacement of the air bag assembly. The test for this
diagnostic trouble code is only run while “AIR BAG”
warning lamp is performing the bulb check. When a
scan tool “Clear Codes” command is issued and the
malfunction is still present, the DTC will not reappear
until the next ignition cycle.


DTC B0016 (Flash Code 16) Passenger Airbag Squib Circuit Low Resistance

Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2 Repeat the “SRS
Diagnostic System
Check”
2

1. Check the passenger air bag squib circuit for short to voltage
or short to ground.

2. If the problem found, repair as necessary.
Was a problem found? Verify repair Go to Step 3
3

1. Ignition switch “Off.”

2. Make sure the passenger air bag assembly yellow connector
located behind the glove box assembly is seated properly.
Is the yellow connector connected properly? Go to Step 4 Seat passenger air
bag assembly
yellow connector
properly.
Go to Step 7
4

1. Disconnect and inspect the passenger air bag assembly
yellow connector located behind the glove box assembly.

2. If ok, reconnect the passenger air bag assembly connector.

3. Ignition switch “ON.”
Is DTC B0016 Current? Go to Step 5 Go to Step 7
5

1. Ignition switch “Off.”

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

3. Connect 5-8840-2421-0 SRS driver/passenger load tool and
appropriate adapters to SRS coil and passenger air bag
assembly harness connectors.

4. Ignition switch “ON.”
Is DTC B0016 current? Go to Step 6 Ignition switch
“Off.”
Replace the
passenger air bag
assembly.
Go to Step 7
6

1. Ignition switch “Off.”

2. There has been a decrease in the total circuit resistance of
the passenger inflator deployment loop
Replace SRS
harness.
Go to Step 7 Go to Chart A

9A1-20 RESTRAINT CONTROL SYSTEM

DTC B0017 (Flash Code 17) Passenger Airbag Squib Circuit High Resistance


RTW49JLF000101

Circuit Description
When the ignition switch is turned “ON”, the SRS
control unit will perform tests to diagnose critical
malfunctions within itself. Upon passing these tests
“Ignition 1”, and deployment loop voltages are
measured to ensure they are within their respective
normal voltage ranges. The SRS control unit then
proceeds with the “Resistance Measurement Test”.
“Passenger Bag Low” terminal “47” is grounded through
a resister and the passenger current source connected
to “Passenger Bag High” terminal “48” allows a known
amount of current to flow. By monitoring the voltage
difference between “Passenger Bag High” and
“Passenger Bag Low” the SRS control unit calculates
the combined resistance of the passenger air bag
assembly, harness wiring circuits “Passenger Bag High”
and “Passenger Bag Low” connector terminal contact.
DTC Will Set When
The combined resistance of the passenger air bag
assembly, harness wiring circuits “Passenger Bag High”
and “Passenger Bag Low”, and connector terminal
contact is above a specified value. This test is run
once each ignition cycle during the “Resistance
Measurement Test” when:
1.
No “higher priority faults” are detected during “Turn–
ON”,
2.
“Ignition 1” voltage is in the specified value.

Action Taken
SRS control unit turns “ON” the “AIR BAG” warning
lamp and sets a diagnostic trouble code.

RESTRAINT CONTROL 9A1-21

DTC Will Clear When
The ignition switch is turned “OFF.”

DTC Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
2.
This test determines whether the malfunction is in
the SRS control unit.
3.
This test verifies proper connection of the yellow
connector.
4.
This test checks for proper contact and/or corrosion
of the yellow connector terminals.
5.
The test checks for a malfunctioning passenger ai
r
bag assembly.
6.
This test determines whether the malfunction is due
to high resistance in the wiring.
Diagnostic Aids
An intermittent condition is likely to be caused by a poor
connection at the passenger air bag assembly harness
connector terminals “1” and “2”, SRS control unit
terminal “48” and “47”, or a poor wire to terminal
connection in circuits “Passenger Bag High” and
“Passenger Bag Low”. This test for this diagnostic
trouble code is only run while the “AIR BAG” warning
lamp is performing the bulb check. When a scan tool
“Clear Codes” command is issued and the malfunction
is still present, the DTC will not reappear until the next
ignition cycle.


DTC B0017 (Flash Code 17) Passenger Airbag Squib Circuit High Resistance

Step Action Yes No
1 Was the “SRS Diagnostic System Check” Performed? Go to Step 2 Go to The “SRS
Diagnostic System
Check”
2

1. Check the passenger air bag squib circuit for open.

2. If the problem found, repair as necessary.
Was a problem found? Verify repair Go to Step 3
3

1. Ignition switch “Off.”

2. Make sure the passenger air bag assembly yellow connector
located behind the glove box assembly is seated properly.
Is the yellow connector connected properly? Go to Step 4 Seat passenger Air
Bag assembly
yellow connector
properly.
Go to Step 7
4

1. Disconnect and inspect the passenger air bag assembly
yellow connector located behind the glove box assembly.

2. If ok, reconnect the passenger air bag assembly connector.
3. Ignition switch “ON.”
Is DTC B0017 current? Go to Step 5 Go to Step 7
5

1. Ignition switch “Off.”

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

3. Connect 5-8840-2421-0 SRS driver / passenger load tool and
appropriate adapters to SRS coil and passenger air bag
assembly harness connectors.

4. Ignition switch “ON.”
Is DTC B0017 Current? Go to Step 6 Ignition switch
“Off.”
Replace the
passenger air bag
assembly.
Go to Step 7

9A1-24 RESTRAINT CONTROL SYSTEM

DTC Will Clear When
This malfunction is no longer occurring and the ignition
switch is turned “OFF”.

DTC Chart Test Description
Number(s) below refer to circled number(s) on the
diagnostic chart.
2.
This test determines whether the SRS control unit is
malfunctioning.
3.
This test isolates the malfunction to one side of the
passenger air bag assembly yellow connector behind
glove box compartment.
4.
This test determines whether the malfunction is in
“Passenger Bag High” circuit.
5.
This test determines whether the malfunction is in
“Passenger Bag Low” circuit.
6.
This test determines whether the malfunction is in
“Driver Bag High” circuit.
7.
This test determines whether the malfunction is in
“Driver Bag Low” circuit.
Diagnostic Aids
An intermittent condition is likely to be caused by a short
to ground/+B in the passenger air bag assembly circuit.
Inspect circuits “Passenger Bag High” and “Passenger
Bag Low” carefully for cutting or chafing. If the wiring
pigtail of the passenger air bag assembly is damaged,
the component must be replaced.


DTC B0018 (Flash Code 18) Passenger Airbag Squib Circuit Voltage Range/Performance

Step Action Yes No
1 Was the “SRS Diagnostic System Check” performed? Go to Step 2 Go to the “SRS
Diagnostic System
Check”
2

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. Ignition switch “ON.”

4. Check the passenger air bag squib circuit for short to voltage,
short to ground and open.
Was a problem found? Go to Step 3


3

1. Ignition switch “OFF.”

2. Disconnect passenger air bag assembly yellow connector
behind the glove box assembly.
3. Leave driver air bag assembly connected.

4. Connect SRS driver / passenger load tool 5-8840-2421-0 and
appropriate adapter to passenger air bag assembly harness
connector.
5. Ignition switch “ON.”
Is DTC B0018 current? Go to Step 4 Ignition switch
“OFF.”
Replace
passenger air bag
assembly .
Go to Step 8
4

1. Ignition switch “OFF”.

2. Disconnect SRS driver / passenger load tool
3. Measure resistance on SRS control unit harness connector
from terminal “48” to terminal “40” (ground).
Does 5-8840-0285-0 display “OL” (Infinite)? Go to Step 5 Replace SRS
Harness.
Go to Step 8
5 Measure resistance on SRS control unit harness connector from
terminal “47” to terminal “40” (ground).
Does 5-8840-0285-0 display “OL” (Infinite)? Go to Step 6
Replace SRS
Harness.
Go to Step 8

9A1-26 RESTRAINT CONTROL SYSTEM

DTC B0022 (Flash Code 22) Driver Airbag Squib Circuit Low Resistance


RTW49JLF000101

Circuit Description
When the ignition switch is turned “ON”, the SRS
control unit will perform tests to diagnose critical
malfunctions within itself. Upon passing these tests
“Ignition 1”, and deployment loop voltages are
measured to ensure they are within their respective
normal voltage ranges.
The SRS control unit then proceeds with the
“Resistance Measurement Test” “Driver Bag Low”
terminal “46” is grounded through a current sink and
the driver current source connected to “Driver Bag
High” terminal “45” allows a known amount of current to
flow. By monitoring the voltage difference between
“Driver Bag High” and “Driver Bag Low” the SRS control
unit calculates the combined resistance of the driver ai
r
bag assembly, SRS coil assembly, harness wiring
circuits “Driver Bag High” and “Driver Bag Low” and
connector terminal contact.

RESTRAINT CONTROL 9A1-27

DTC Will Set When
The combined resistance of the driver air bag
assembly, SRS Coil assembly, harness wiring circuits
“Driver Bag High” and “Driver Bag Low”, and connector
terminal contact is above a specified value. This test is
run once each ignition cycle during the “Resistance
Measurement Test” when:
1.
No “higher priority faults” are detected during “Turn–
ON”
2.
“Ignition 1” voltage is in the specified value.

Action Taken
SRS control unit turns “ON” the “AIR BAG” warning
lamp and sets DTC B0022.

DTC Will Clear When
The ignition switch is turned “OFF.”
DTC Chart Test Description
Number(s) below refer to circled number(s) on the
diagnostic chart:
2.
This test determines whether the malfunction is in
the SRS control unit.
3.
This test verifies proper connection of the yellow
connector at the base of the steering column.
4.
This test checks for proper operation of the shorting
clip in the yellow connector.
5.
This test isolate the malfunction to one side of the
SRS coil assembly yellow connector located at the
base of steering column.
6.
This test determines whether the malfunction is due
to shortening in the wiring.
7.
This test determines whether the malfunction is in
the SRS coil assembly or the driver air bag
assembly.

Diagnostic Aids
An intermittent condition is likely to be caused by a short
between circuit “Driver Bag High” or “Driver Bag Low”
or a malfunctioning shorting clip on the driver air bag
assembly or SRS coil assembly which would require
replacement of the component. The test for this
diagnostic trouble code is only run while the “AIR BAG”
warning lamp is performing the bulb check. When a
scan tool “Clear Codes” command is issued and the
malfunction is still present, the DTC will not reappear
until the next ignition cycle.


DTC B0022 (Flash Code 22) Driver Airbag Squib Circuit Low Resistance

Step Action Yes No
1 Perform the “SRS Diagnostic System Check.”
Was the “SRS Diagnostic System Check” performed? Go to Step 2 Go to the “SRS
Diagnostic System
Check”
2

1. Check the driver air bag squib circuit for short to voltage or
short to ground.

2. If the problem found, repair as necessary.
Was a problem found? Verify repair Go to Step 3
3

1. Ignition switch “OFF.”

2. Make sure the SRS coil assembly yellow connector located
at the base of steering column is seated properly.
Is the connector connected properly? Go to Step 4 Seat driver air bag
assembly
connector
properly.
Go to Step 8
4

1. Disconnect and inspect the SRS coil assembly yellow
connector located base of steering column.

2. If ok, reconnect the SRS coil assembly yellow connector.

3. Ignition switch “ON.”
Is DTC B0022 current? Go to Step 5 Go to Step 8

9A1-32 RESTRAINT CONTROL SYSTEM

DTC B0026 (Flash Code 26) Driver Airbag Squib Circuit High Resistance


RTW49JLF000101

Circuit Description
When the ignition switch is turned “ON”, the SRS
control unit will perform tests to diagnose critical
malfunctions within itself. Upon passing these tests,
“Ignition 1”, and deployment loop voltages are
measured to ensure they are within their respective
normal voltage ranges.
The SRS control unit then proceeds with the
“Resistance Measurement Test” “Driver Bag Low”
terminal “46” is grounded through a current sink and the
driver current source connected to “Driver Bag High”
terminal “45” allows a known amount of current to flow.
By monitoring the voltage difference between “Drive
r
Bag High” and “Driver Bag Low”, the SRS control unit
calculates the combined resistance of the driver air bag
assembly, SRS coil assembly, harness wiring circuits
“Driver Bag High” and “Driver Bag Low” and connecto
r
terminal contact.

RESTRAINT CONTROL 9A1-33

DTC Will Set When
The combined resistance of the driver air bag
assembly, SRS Coil assembly, harness wiring circuits
“Driver Bag High” and “Driver Bag Low”, and connector
terminal contact is above a specified value. This test
run once each ignition cycle during the “Resistance
Measurement Test” when:
1.
No “higher priority faults” are detected during “Turn–
ON”
2.
“Ignition 1” voltage is in the specified value.

Action Taken
SRS control unit turns “ON” the “AIR BAG” warning
lamp and sets DTC B0026.

DTC Will Clear When
The ignition switch is turned “OFF”.



DTC Chart Test Description
Number(s) below refer to step number(s) on the
diagnostic chart:
2.
This test determines whether the malfunction is in
the SRS control unit.
3.
This test verifies proper connection of the yellow
connector at the base of the steering column.
4.
This test checks for proper contact and/or corrosion
of the connector terminals at the base of steering
column.
5.
This test isolate the malfunction to one side of the
SRS coil assembly yellow connector located at the
base of the steering column.
6.
This test determines whether the malfunction is due
to high resistance in the wiring.
7.
This test determines whether the malfunction is in
the SRS coil assembly or the driver air bag
assembly.

Diagnostic Aids
An intermittent condition is likely to be caused by a poor
connection at terminals “1” and “2” of the SRS coil
connector at the base of the steering column, terminal
“1” and “2” of the driver air bag assembly connector at
the top of the steering column, SRS control unit
terminals “45” and “46” or a poor wire to terminal
connection in circuit “Driver Bag High” or “Driver Bag
Low” The test for this diagnostic trouble code is onl
y
run while the “AIR BAG” warning lamp is performing
the bulb check. When a scan tool “Clear Codes”
command is issued and the malfunction is still present,
the DTC will not reappear until the next ignition cycle.

DTC B0026 (Flash Code 26) Driver Airbag Squib Circuit High Resistance

Step Action Yes No
1 Perform the “SRS Diagnostic System Check”.
Was the “SRS Diagnostic System Check” performed? Go to Step 2 Repeat the “SRS
Diagnostic System
Check”
2

1. Check the driver air bag squib circuit for open.

2. If the problem found, repair as necessary.
Was a problem found? Verify repair Go to Step 3
3

1. Ignition switch “OFF.”

2. Disconnect SRS coil assembly yellow connector located at
base of steering column is seated properly.
Is the connector connected properly? Go to Step 4 Seat SRS coil
assembly
connector
properly.
Go to Step 8