ISUZU TROOPER 1998 Service Repair Manual

RESTRAINT CONTROL SYSTEM 9J1±14
warning lamp is performing the bulb check, unless DTC
17 or DTC 26 is detected. When a scan tool ªClear
Codesº command is issued and the malfunction is stillpresent, the DTC will not reappear until the next ignition
cycle.
DTC 15 Passenger Deployment loop Resistance High
StepActionYe sNo
1Was the ªSRS Diagnostic System Checkº Performed?
Go to Step 2
Go to The ªSRS
Diagnostic
System Checkº
21. When measurements are requested in this chart use
5±8840±0285±0 DVM with correct terminal adapter from
5±8840±0385±0.
2. Use scan tool data list function, read and record the passenger
deployment loop resistance.
Is passenger resist. more than 2.9 ohms?
Go to Step 3Go to Chart A
31. Ignition switch ªOff.º
2. Make sure the passenger air bag assembly yellow 2±pin
connector located behind the glove box assembly is seated
properly.
Is the yellow 2±pin connector connected properly?
Go to Step 4
Seat passenger
Air Bag assembly
yellow 2±pin
connector
properly
Go to Step 7
41. Disconnect and inspect the passenger air bag assembly
yellow 2±pin connector located behind the glove box
assembly.
2. If ok, reconnect the passenger air bag assembly 2±pin
connector.
3. Ignition switch ªON.º
Is DTC 15 current?
Go to Step 5Go to Step 7
51. Ignition switch ªOff.º
2. Disconnect SRS coil and passenger air bag assembly, yellow
2±pin 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 ªON.º
Is DTC 15 Current?
Go to Step 6
Ignition switch
ªOffº
Replace the
passenger air
bag assembly
Go to Step 7
61. Ignition switch ªOff.º
2. There has been an increase in the total circuit resistance of the
passenger inflator deployment loop.
3. Use the high resolution ohmmeter mode of the DVM while
checking IB07±YEL/GRN and IB08±YEL/RED, and SDM
connector terminal ª15º and ª16º to locate the root cause.
Was a fault found?
Replace SRS
harness
Go to Step 7
Go to Chart A
71. Reconnect all components ensure all component are properly
mounted.
2. Clear diagnostic trouble codes.
Was This step finished?
Repeat the ªSRS
Diagnostic
System Checkº
Go to Step 7

9J1±15
RESTRAINT CONTROL SYSTEM
DTC 16 Passenger Deployment loop Resistance Low
D09RW014
Circuit Description:
When the ignition switch is turned ªONº, the SDM will
perform tests to diagnose critical malfunctions within
itself. Upon passing these tests ªIgnition 1º, and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges. The
SDM then proceeds with the ªResistance Measurement
Testº. ªPassenger Bag Lowº terminal ª16º is grounded
through a resistor and the passenger current source
connected to ªPassenger Bag Highº terminal ª15º allows a
known amount of current to flow. By monitoring the
voltage difference between ªPassenger Bag Highº and
ªPassenger Bag Lowº, the SDM calculates the combined
resistance of the passenger air bag assembly, harness
wiring IB07±YEL/GRN and IB08±YEL/RED connector
terminal contact.
DTC Will Set When:
The combined resistance of the passenger air bag
assembly, harness wiring IB07±YEL/GRN and
IB08±YEL/RED, and connector terminal contact is above
a specified value. This test is run once each ignition cycle
during the ªResistance Measurement Testº when:
1. No ªhigher priority faultsº are detected during
ªTurn±ONº,
2. ªIgnition 1º voltage is in the specified value.
Action Taken:
SDM turns ªONº the ªAIR BAGº warning lamp and sets a
diagnostic trouble code.
DTC Will Clear When:
The ignition switch is turned ªOFF.º
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 SDM.
3. This test verifies connection of the yellow 2±pin
connector.
4. This test cheeks for proper operation of the shorting
clip in the yellow 2±pin 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 IB07±YEL/GRN and IB08±YEL/RED, 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 ªAIR BAGº warning lamp is performing the bulb

RESTRAINT CONTROL SYSTEM 9J1±16
check, unless DTC 17 or DTC 26 is detected. When a
scan tool ªClear Codesº command is issued and themalfunction is still present, the DTC will not reappear until
the next ignition cycle.
DTC 16 Passenger Deployment loop Resistance Low
StepActionYe sNo
1Was the ªSRS Diagnostic System Checkº performed?
Go to Step 2
Repeat the ªSRS
Diagnostic
System Checkº
21. When measurements are requested in this chart use
5±8840±0285±0 DVM with correct terminal adapter from
5±8840±0385±0.
2. Using scan tool data list function, read and record the
passenger deployment loop resistance.
Is passenger resist. less than 1.4 ohms?
Go to Step 3Go to Chart A
31. Ignition switch ªOff.º
2. Make sure the passenger air bag assembly yellow 2±pin
connector located behind the glove box assembly is seated
properly.
Is the yellow 2±pin connector connected properly?
Go to Step 4
Seat passenger
air bag assembly
yellow 2±pin
connector
properly
Go to Step 7
41. Disconnect and inspect the passenger air bag assembly
yellow 2±pin connector located behind the glove box
assembly.
2. If ok, reconnect the passenger air bag assembly 2±pin
connector.
3. Ignition switch ªON.º
Is DTC 16 Current?
Go to Step 5Go to Step 7
51. Ignition switch ªOff.º
2. Disconnect SRS coil and passenger air bag assembly, yellow
2±pin 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 ªON.º
Is DTC 16 current?
Go to Step 6
Ignition switch
ªOffº
Replace the
passenger air
bag assembly
Go to Step 7
61. Ignition switch ªOff.º
2. There has been a decrease in the total circuit resistance of the
passenger inflator deployment loop.
3. Use the high resolution ohmmeter mode of the DVM while
checking IB07±YEL/GRN and IB08±YEL/RED, and SDM
connector terminal ª15º and ª16º to locate the root cause.
Was a fault found?
Replace SRS
harness
Go to Step 7
Go to Chart A
71. Reconnect all components, ensure all component are properly
mounted.
2. Clear diagnostic trouble codes.
Was this step finished?
Repeat the ªSRS
Diagnostic
System Checkº
Go to Step 7

9J1±17
RESTRAINT CONTROL SYSTEM
DTC 17 Passenger Deployment Loop Open
D09RW014
Circuit Description:
When the ignition switch is turned ªONº, the SDM will
perform tests to diagnose critical malfunctions within
itself. Upon passing these tests, ªIgnition 1º, and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges. During
ªContinuous Monitoringº diagnostics, a fixed amount of
current is flowing in the deployment loop. This produces
proportional voltage drops in the loop. By monitoring the
voltage difference between ªPassenger Bag Highº and
ªPassenger Bag Lowº, the SDM calculates the combined
resistance of the passenger air bag assembly, harness
wiring IB07±YEL/GRN AND IB08±YEL/RED, and
connector terminal contact.
DTC Will Set When:
The voltage difference between ªPassenger Bag Highº
terminal ª15º and ªPassenger Bag Lowº terminal ª16º is
above or equal to a specified value for 500 milliseconds
during ªContinuous Monitoringº.
Action Taken:
SDM turns ªONº the ªAIR BAGº warning lamp and sets a
diagnostic trouble code.
DTC Will Clear When:
The voltage difference between ªPassenger Bag Highº
terminal ª15º and ªPassenger Bag Lowº terminal ª16º is
below a specified value for 500 milliseconds during
ªContinuous Monitoringº.
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 SDM.
3. This test verifies proper connection of the yellow
2±pin connector.
4. This test cheeks for proper contact and/or corrosion
of the shorting clip in the yellow 2±pin connector
terminals.
5. The test checks for a malfunctioning passenger air
bag assembly.
6. This test determines whether the open 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 terminalsª2º and ª3º, SDM terminals ª15º and
ª16º, or an open in IB07±YEL/GRN and IB08±YEL/RED.

RESTRAINT CONTROL SYSTEM 9J1±18
DTC 17 Passenger Deployment Loop Open
StepActionYe sNo
1Was the ªSRS Diagnostic System Checkº performed?
Go to Step 2
Go to the ªSRS
Diagnostic
System Checkº
21. When measurements are requested in this chart use
5±8840±0285±0 DVM with correct terminal adapter from
5±8840±0385±0.
2. Using scan tool data list function, read and record the
passenger differential voltage.
Is passenger VDIF 0.425 volts or more?
Go to Step 3Go to Chart A
31. Ignition switch ªOFFº.
2. Make sure the passenger air bag assembly yellow 2±pin
connector located behind the glove box assembly is seated
properly.
Is the yellow 2±pin connector connected properly?
Go to Step 4
Seat passenger
air bag assembly
yellow 2±pin
connector
properly
Go to Step 7
41. Disconnect and inspect the passenger air bag assembly
yellow 2±pin connector located behind the glove box
assembly.
2. If ok, reconnect the passenger air bag assembly 2±pin
connector.
3. Ignition switch ªONº.
Is DTC 17 current?
Go to Step 5Go to Step 7
51. Ignition switch ªOff.º
2. Disconnect SRS coil and passenger air bag assembly, yellow
2±pin 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 ªON.º
Is DTC 17 current?
Go to Step 6
Ignition switch
ªOffº
Replace the
passenger air
bag assembly
Go to Step 7
61. Ignition switch ªOff.º
2. There has been an open circuit resistance in the passenger
deployment loop.
3. Use the high resolution ohmmeter mode of the DVM while
checking IB07±YEL/GRN and IB08±YEL/RED, and SDM
connector terminal ª15º and ª16º to locate the root cause.
Was a fault found?
Replace SRS
harness
Go to Step 7
Go to Chart A
71. Reconnect all components ensure all component are properly
mounted.
2. Clear diagnostic trouble codes.
Was this step finished?
Go to the ªSRS
Diagnostic
System Checkº
Go to Step 7

9J1±19
RESTRAINT CONTROL SYSTEM
DTC 18 Passenger Deployment Loop Short To Ground
D09RW014
Circuit Description:
When the ignition switch is turned ªONº, the SDM will
perform tests to diagnose critical malfunctions within
itself. Upon passing these tests, ªIgnition 1º, and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges.
The SDM monitors the voltages at ªDriver Bag Lowº
terminal ª4º and ªPassenger Bag Lowº terminal ª16º to
detect short to ground in the air bag assembly circuits.
DTC Will Set When:
Neither of the two air bag assemblies is open.
ªIgnition 1º is within the normal operating voltage range.
Once these conditions are met and the voltage at
ªPassenger Bag Lowº is below a specified value, DTC 18
will set. This test is run once each ignition cycle and
ªContinuous Monitoringº.
Action Taken:
SDM turns ªONº the ªAIR BAGº warning lamp and sets a
diagnostic trouble code.
DTC Will Clear When:
This malfunction is no longer occurring and the ignition
switch is turned ªOFFº.
DTC Chart Test Description:
Number(s) below refer to circled number(s) on the
diagnostic chart.
2. This test determines whether the SDM is
malfunctioning.
3. This test isolates the malfunction to one side of the
passenger air bag assembly yellow 2±pin connector
behind glove box assembly.
4. This test determines whether the malfunction is in
IB07±YEL/GRN.
5. This test determines whether the malfunction is in
IB08±YEL/RED.
Diagnostic Aids:
An intermittent condition is likely to be caused by a short
to ground in the passenger air bag assembly circuit.
Inspect IB07±YEL/GRN and IB08±YEL/RED carefully for
cutting or chafing. If the wiring pigtail of the passenger air
bag assembly is damaged, the component must be
replaced.

RESTRAINT CONTROL SYSTEM 9J1±20
DTC 18 Passenger Deployment Loop Short To Ground
StepActionYe sNo
1Was the ªSRS Diagnostic System Checkº performed?
Go to Step 2
Go to the ªSRS
Diagnostic
System Checkº
21. 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 ªOFF.º
3. Connect scan tool data link connector. follow directions as
given in the scan tool operator's MANUAL.
4. Ignition switch ªON.º
5. Read passenger bag sense LO.
Is passenger bag sense LO less than 1.5 volts?
Go to Step 3Go to Chart A
31. Ignition switch ªOFF.º
2. Disconnect passenger air bag assembly yellow 2±pin
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 ªON.º
Is DTC 18 current?
Go to Step 4
Ignition switch
ªOFFº
Replace
passenger air
bag assembly
Go to Step 6
41. Ignition switch ªOFFº.
2. Disconnect SRS driver / passenger load tool
3. Measure resistance on SDM harness connector from terminal
ª15º to terminal ª16º (ground).
Does 5±8840±0285±0 display ªOLº (Infinite)?
Go to Step 5
Replace SRS
Harness
Go to Step 6
5Measure resistance on SDM harness connector from terminal
ª16º to terminal ª6º (ground).
Does 5±8840±0285±0 display ªOLº (Infinite)?
Go to Chart A
Replace SRS
Harness.
Go to Step 6
61. Reconnect all components and ensure all component are
properly mounted.
2. Clear diagnostic trouble codes.
Was this step finished?
Go to the ªSRS
Diagnostic
system Checkº
Go to Step 6

9J1±21
RESTRAINT CONTROL SYSTEM
DTC 19 Passenger Deployment Loop Short To B+
D09RW014
Circuit Description:
When the ignition switch is turned ªONº, the SDM will
perform tests to diagnose critical malfunctions within
itself. Upon passing these tests, ªIgnition 1º, and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges.
The SDM monitors the voltages at ªDriver Bag Lowº
terminal ª4º and ªPassenger Bag Lowº terminal ª16º to
detect short to B+ in the air bag assembly circuits.
DTC Will Set When:
ªIgnition 1º is within the normal operating voltage range.
Once these conditions are met and the voltage at
ªPassenger Bag Lowº is above a specified value, DTC 19
will set. This test is run once each ignition cycle and
ªContinuous Monitoringº.
Action Taken:
SDM turns ªONº the ªAIR BAGº warning lamp and sets
DTC 19 and also DTC 71.
DTC Will Clear When:
The SDM is replaced.
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 SDM.
3. This test isolates the malfunction to one side of the
passenger air bag assembly yellow 2±pin connector
behind glove box assembly.
4. This test determines whether the malfunction is in
IB07±YEL/GRN.
5. This test determines whether the malfunction is in
IB08±YEL/RED.
Diagnostic Aids:
An intermittent condition is likely to be caused by a short
to B+ in the passenger air bag assembly circuit. Inspect
IB07±YEL/GRN and IB08±YEL/RED carefully for cutting
or chafing. If the wiring pigtail of the passenger air bag
assembly is damaged, the component must be replaced.
A careful inspection of IB07±YEL/GRN and
IB08±YEL/RED, including the passenger air bag
assembly pigtail is essential to ensure that the
replacement SDM will not be damaged.

RESTRAINT CONTROL SYSTEM 9J1±22
DTC 19 Passenger Deployment Loop Short To B+
CAUTION: When DTC 19 has been set, it is necessary to replace the SDM. Setting DTC 19 will also cause DTC
71 to set. When a scan tool ªCLEAR CODESº command is issued and the malfunction is no longer present,
DTC 71 will remain current. Ensure that the short to voltage condition is repaired prior to installing a
replacement SDM to avoid damaging the SDM.
Step
ActionYe sNo
1Perform the ªSRS Diagnostic System Checkº
Was the ªSRS Diagnostic System Checkº performed?
Go to Step 2
Repeat the ªSRS
Diagnostic
System Checkº
21. 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 ªOFF.º
3. Connect scan tool data link connector. follow directions as
given in the scan tool operator's manual.
4. Ignition switch ªON.º
5. Read passenger bag sense LO.
Is passenger bag sense LO more than 3.5 volts?
Go to Step 3Go to Chart A
31. Ignition switch ªOFFº.
2. Disconnect passenger air bag assembly yellow 2±pin
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 ªON.º
Is passenger bag sense LO more than 3.5 volts?
Go to Step 4
Ignition switch
ªOFFº
Replace
passenger air
bag assembly
Go to Step 6
41. Ignition switch ªOFF.º
2. Disconnect SDM.
3. Disconnect SRS driver / passenger load tool.
4. Measure resistance on SDM harness connector from terminal
ª15º to terminal ª12º (ignition).
Does 5±8840±0285±0 display ªOLº (infinite)?
Go to Step 5
Replace SRS
harness
Go to Step 6.
5Measure resistance on SDM harness connector from terminal
ª16º and terminal ª12º (ignition).
Does 5±8840±0285±0 display ªOLº (infinite)?
Go to Chart A
replace SRS
harness
Go to Step 6
61. Reconnect all components ensure all component are properly
mounted.
2. Ignition switch ªONº.
Is passenger bag senslo less than 3.5 volts?Ignition switch
ªOFFº
Replace SDM
Go to Step 7
Go to Chart A
71. Reconnect all components ensure all component are properly
mounted.
2. Clear diagnostic trouble codes.
Was this step finished?
Repeat the ªSRS
Diagnostic
System Checkº
Go to Step 7

9J1±23
RESTRAINT CONTROL SYSTEM
DTC 21 Driver Deployment Loop Resistance High
D09RW014
Circuit Description:
When the ignition switch is turned ªONº, the SDM will
perform tests to diagnose critical malfunctions within
itself. Upon passing these tests, ªIgnition 1º, and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges.
The SDM then proceeds with the ªResistance
Measurement Testº ªDriver Bag Lowº terminal ª4º is
grounded through a current sink and the driver current
source connected to ªDriver Bag Highº terminal ª3º allows
a known amount of current to flow. By monitoring the
voltage difference between ªDriver Bag Highº and ªDriver
Bag Lowº, the SDM calculates the combined resistance
of the driver air bag assembly, SRS coil assembly,
harness wiring IB05±YEL and IB06±YEL/BLK, and
connector terminal contact.
DTC Will Set When:
The combined resistance of the driver air bag assembly,
SRS Coil assembly, harness wiring IB05±YEL and
IB06±YEL/BLK, and connector terminal contact is above
a specified value. This test run once each ignition cycle
during the ªResistance Measurement Testº when:
1. No ªhigher priority faultsº are detected during
ªTurn±ONº
2. ªIgnition 1º voltage is in the specified value.
Action Taken:
SDM turns ªONº the ªAIR BAGº warning lamp and sets
DTC 21.
DTC Will Clear When:
The ignition switch is turned ªOFFº.
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 SDM.
3. This test verifies proper connection of the yellow
2±pin connector at the base of the steering column.
4. This test checks for proper contact and/or corrosion
of the 2±pin connector terminals at the base of
steering column.
5. This test isolate the malfunction to one side of the
SRS coil assembly yellow 2±pin 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.