warning ISUZU TROOPER 1995 Workshop Manual

9J-48 Supplemental Restraint System

DTC 17
PASSENGER INITIATOR CIRCUIT OPEN
CIRCUIT DESCRIPTION
When there is an open in the passenger inflator module,
the resistance between "Passenger
Side High" terminal
"A7'' and "Passenger
Side Low'' terminal "87" increases.
This causes a larger voltage drop from the"Passenger
Side High" to the "Passenger Side Low" across a resistor
inside the DERM which connects these two terminals
together. The increase
in the voltage difference between
"Passenger
Side High" and "Passenger Side Low" is
detected by the DERM during the "Continuous
Monitoring" tests and DTC 17 is set.
DTC WILL SET WHEN
The voltage difference between "Passenger Side High"
terminal "A
7" and "Passenger Side Low" terminal "87" is
above
or equal to a specified value for 500 milliseconds.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic trouble code.
FUSE TO~~~WN -.:.:SR;=.S~C·;:e23,..:.:10::..:.A_-P
!~l lOA 1100 D
....
DTC WILL CLEAR WHEN
The voltage difference between "Passenger Side High"
terminal "A"f' and "Passenger Side Low'' terminal "B7" is
below a specified value for
500 milliseconds.
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 passenger inflator module circuitry.
DIAGNOSTIC AIDS
This diagnostic trouble code will only set when there is
an
improper connection to the passenger inflator
module, an improper connection to the passenger
inflator module jumper or an open in the passenger
inflator module or pigtail.
SRS-1 JOINT CONNECTION 10 1101 IGNITION1
IGNITION 1 DRIVER SOURCE SENSE DRIVER 38VLR PASS.38VLR PASS. SOURCE SENSE
REDUNDAT INDICATOR GROUND
PASS SIDE HIGH
PASS SIDE LOW
SPARE/LPS
SERIAL DATA
SRS INDICATOR
•

9J-50 Supplemental Restraint System
DTC 18
DISCRIMINATING SENSOR INTERCONNECT PEN
CIRCUIT DESCRIPTION
During the "Initiator Assembly Resistance Test" the
DERM grounds the "Driver
Side Low" terminal "88" and
measures the voltage at "Driver Side Low" and
"Passenger Side Low." The DERM then grounds
"Passenger Side Low" terminal "87" and again measures
the voltage at "Driver
Side Low" and "Passenger Side
Low."For a properly operating circuit the voltage
measurements during each of these tests will be below
a specified value. When the voltage measured at either
"Driver
Side Low" or "Passenger Side Low," but not both,
is above a specified value during either test
DTC 18 is
set.
DTC WILL SET WHEN
The voltage measured at either "Driver Side Low" or
"Passenger
Side Low," but not both, is above a specified
value
while the DERM attempts to ground either of these
terminals. This test is run during the
"Initiator Assembly
Resistance
Tesf' and the "1 o Minute Loop Test" when: 1)
No "higher priority faults" are detected during "Turn-ON,"
2) No "higher priority faults" are detected during
"Continuous Monitoring" for one second, 3) No "Crank"
signal present, 4) "Ignition 1" voltage is above a specified
value.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic trouble code.
DTC WILL CLEAR WHEN
The voltages measured at both "Driver Side Low" and
"Passenger
Side Low" are below specified value while
the DERM grounds each of the terminals.
DTC CHART TEST. DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
2. This test checks .whether the malfunction is in the
wiring harness. The wiring. harness malfunction is in
the wiring harness. The wiring harness malfunction
world be a high resistance rather than an open. An
open would sets a different diagnostic trouble code.
DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a poor
connection
in JOINT CONNECTOR SRS-2. When a
scan tool
"Clear Codes" command is issued and the
malfunction is
still present, the DTC will not reappear for
ten minutes or
until the next ignition cycle.
IGNITION1
DRIVER 3liVLR
PASS.38VLR
PASS; SOURCE SENSE
REDUNDAT INDICATOR GROUND
PASS SIDE HIGH
PASS SIDE LOW
SPARE/LPS
SERIAL DATA
SRS INDICATOR
•

9J-52 Supplemental Restraint System
DTC 19
PASSENGER INITIATOR CIRCUIT VOLTAGE HIGH
CIRCUIT DESCRIPTION
During normal, non-deployment operation of the SRS,
a small amount of current flows through both the driver
and passenger deployment loops. The diagnostic
resistors within the dual pole arming sensor and the
discriminating sensors
along with the resistance of the
inflator modules cause voltage drops within the
deployment loops. The DERM monitors the voltage at
"Passenger
Side Low" terminal "87" to detect shorts or
opens within the passenger deployment
loop. When the
measured
voltage is above a specified percentage of
"Passenger 36
VLR" for 500 milliseconds DTC 19 is set.
DTC WILL SET WHEN
The voltage measured at "Passenger Side Low'' terminal
"87''
is above a specified percentage of "Passenger 36
VLR" for 500 milliseconds and DTC 35 is not set. This
test is
run every 100 milliseconds during the "Continuous
Monitoring" tests.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic
trouble code.
DTC WILL CLEAR WHEN
The voltage measured at "Passenger Side Low" terminal
"87"
is within a specified percentage of "Passenger 36
VLR" for
500 milliseconds.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
2. DTC 19 and 23 together means that there is both
open Forward
Sensor LH and Forward Sensor RH,
or internal short in dual pole arming sensor.
3. This test checks for decreased resistance in driver
side diagnostic resistors of the
dual pole arming
sensor.
4. This test checks for decreased resistance in the
passenger side diagnostic resistors of the
dual pole
arming sensor.
5. This test determines whether the malfunction is in
the Forward
Sensor RH/LH circuitry.
7. This test determines whether the malfunction is in
the FORWARD SENSOR RH/LH ENG, ROOM
HARNESS or FORWARD SENSOR RHILH.
1
o. This test determines whether the malfunction is in
the
FORWARD SENSOR RH/LH.
DIAGNOSTIC AIDS
An open between the passenger inflator module and the
forward discriminating sensor causes the
voltage to
increase at "Passenger Side Low'' due to the loss of a
ground path. This
also causes the voltage to decrease at
"Driver Side Low" due to decreased current flow through
the discriminating sensor network.
Intermittent condition
is
likely to be caused by backed out shorted terminals on
the arming sensor harness connector, poor connection
at any of the discriminating sensor terminals.
•

9J-54 Supplemental Restraint System
DTC21
DRIVER INITIATOR CIRCUIT RESISTANCE HIGH
CIRCUIT DESCRIPTION
During the "Initiator Assembly resistance Test" the
DERM grounds the
"Passenger Side Low" terminal "B7"
and turns "ON" the driver current source at

the
"Driver
Side
High" terminal "B9". This causes a known amount
of Current to flow through the driver initiator circuit. By
monitoring the difference between the voltage at the
"Driver Side High" terminal "B9" and the "Driver Side
Low'' terminal "B8" the DERM calculates the combined
resistance of the driver inflator module, SRS coil
assembly, harness wiring CKTs IB16, IB17 and IB19 and
connector terminal contact.
DTC WILL SET WHEN
The combined resistance of the driver inflator module,
SRScoilassembly, harness wiring
CKT's IB16, IB17 and
IB19 and connector terminal contact is above a specified
value. This test is run during the
"Initiator Assembly
Resistance
Test" when: 1) No "higher priority faults" are
detected during
"Turn-QN," 2) No "higher priority faults"
are detected during
"Continuous Monitoring" for one
second, 3) No
"Crank" signal present, 4) "Ignition 1"
voltage is above a specified value.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
diagnostic trouble code.
FUSE
TO IGNITION SRS C-2310A 11105 SWITCH
TO
IGNITlON SWITCH
~i SRS
C-24 lOA 1800 AD
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 driver inflator module circuitry or
in the DERM
wiring harness circuitry.
3. This test determines whether the malfunction is an
open in IB19.
DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a poor
connection at: the yellow
2-way connector near the base
of the steering column, DERM terminals
"B8" or "B9", or
the connection at the top of steering column to the driver
inflator module.
SRS·l JOINT CONNECTION
" FUSE SRS C-2210A
BL ED
1800
1807 1111 1812 1113 11114
IGNITION! IGNITION 1
DRIVER 36VLR PASS. 36VLR PASS. SOURCE
SENSE
REDUNDAT INDICATOR GROUND
SRS·1 PASS SIDE HIGH
PASS SIDE LOW
IB34
1831 FUSE STARTER C-10A
SERIAL DATA FUSE
11120
1803
SRS INDICA TOR
•

9J-56 Supplemental Restraint System
DTC22
DRIVER INITIATOR CIRCUIT RESISTANCE LOW
CIRCUIT DESCRIPTION
During the "Initiator Assembly resistance Test" the
DERM grounds the "Passenger
Side Low" terminal "B7"
and turns "ON" the driver current source at the "Driver
Side High" terminal "B9". This causes a known amount
of current to flow through the driver initiator circuit. By
monitoring the difference between the voltage at the
"Driver Side High" terminal "B9" and the "Driver Side
Low"
terminal "B8" the DERM calculates the combined
resistance of the driver inflator module, SRS coil
assembly, harness wiring CKTs IB16, IB17 and IB19 and
connector terminal contact.
DTC WILL SET WHEN
The combined resistance of the driver inflator module,
SRS coil assembly, harness wiring CKT's IB16, IB17 and
IB19 and connector terminal contact is above a specified
value. This test is run during the
"Initiator Assembly
Resistance
Test" when: 1) No "higher priority faults" are
detected during
"Turn-ON," 2) No "higher priority faults"
are detected during "Continuous Monitoring" for one
second,
3) No "Crank" signal present, 4) "Ignition 1"
voltage is above a specified value.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
diagnostic trouble code.
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. DTC 16 and 22 will set simultaneously when the
"Driver Side High" circuit due to parallel current
paths.
3. This test determines whether the malfunction is in
the driver inflator module circuitry or in the DERM
wiring harness circuitry.
4. This test checks for a short from the "Driver Side
High"
circuit to the "Driver Side Low'' circuit.
DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a short
between CKT
IB17 and CKT IB16 or CKT IB19 or a
malfunctioning shorting
clip at the base of the steering
column. 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.
SAS·1 JOINT CONNECTlON FUSE SASC-2310A -. IGNITION 1 IGJ,\\oN FUSE SWrrtH SRS C-22 10A
DRIVER 38VLR PASS.30VLA PASS. SOURCE SENSE
REDUNOAT INOtcATOR GROUND
PASS SIDE HIGH PASS SIDE LOW
SPAREAPS
SERIAL DATA
DRIVER SIDE HIGH DRIVER SIDE LOW REDUNDANT INDICATOR
IGNITION 1
SRS INDICATOR
..

9J-58 Supplemental Restraint System
DTC23
DRIVER INITIATOR CIRCUIT VOLTAGE HIGH
CIRCUIT DESCRIPTION
During normal, non-deployment operation of the SRS,
a small amount of current flows through both the driver
and passenger deployment loops. The diagnostic
resistors within the dual pole arming sensor and the
discriminating sensors
along with the resistance of the
inflator modules cause voltage drops within the
deployment loops. The DERM monitors the voltage at
"Driver Side
Low" terminal "88" to detect shorts or opens
within the driver
deployment loop. When the measured
voltage is above a specified percentage of "Driver 36
VLR for
500 milliseconds DTC 23 is set.
DTC WILL SET WHEN
The voltage measured at "Driver Side Low" terminal "88"
is above a specified percentage of "Driver 36 VLR" for
500 milliseconds and DTC 35 is not set. This test is run
during the
"Continuous Monitoring" tests.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic trouble code.
DTC WILL CLEAR WHEN
The voltage measured at "Driver Side Low" terminal "88"
is within a specified percentage of "Driver 36 VLR" for
500 milliseconds.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
2. DTC 19 and 23 together means that there is both
open FORWARD
SENSOR LH and FORWARD
SENSOR RH, or internal short in dual pole arming
sensor.
3. This test determines whether the
malfunction is an
open in SRS HARNESS.
DIAGNOSTIC AIDS
An open between the driver inflator module harness
connector and the discriminating sensor interconnect
causes the
voltage to increase at "Driver Side Low" due
to the
loss of a ground path. This also causes the voltage
to decrease at "Passenger Side Low'' due to decreased
current
flow through the discriminating sensor network.
OERM
IGNITION 1
IGNITION 1 DRIVER SOURCE SENSE DRIVER 38VLR PASS. 38VLR PASS. SOURCE SENSE
REDUNDAT INDICATOR GROUND
PASS SIDE HIGH
PASS SIDE LOW
SRS INDICATOR
•

9J-60 Supplemental Restraint System


DTC 24 {PAGE 1 OF 3)
INITIATOR CIRCUIT VOLTAGE LOW
' I,
CIRCUIT DESCRIPTION
During normal, non-deployment operation of the SRS,
a small amount of current flows through both the driver
and passenger deployment loops. The diagnostic
resistors within the dual pole arming sensor and the
discriminating sensors
along with the resistance of the
inflator modules cause voltage drops within the
deployment loops. The DERM monitors the voltage at
"Driver Side Low" terminal "88" and "Passenger Side
Low" terminal "87" to detect shorts or opens within the
driver deployment
loop. When the measured voltage at
terminal "88" or "87" is below a specified percentage of
its respective Driver 36 VLR power
supply voltage for
500 milliseconds DTC 24 is set.
DTC WILL SET WHEN
The voltage measured at "Driver Side Low" terminal "88"
is below a specified percentage of "Driver 36 VLR" or
when the
voltage measured at "Passenger Side Low"
terminal "87" is below a specified percentage of
"Passenger 36 VLR" for 500 milliseconds. This test is run
during the "Continuous Monitoring" test.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic
trouble code.
DTC WILL CLEAR WHEN
The voltage measured at "Driver Side Low" terminal "88"
is within a specified percentage of "Driver 36 VLR" and
the
voltage measured at "Passenger Side Low" terminal
"87"
is within a specified percentage of "Passenger 36
VLR" for 500 milliseconds.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
2. This test determines whether the malfunction is
occurring
in the steering column circuitry.
3. This test determines whether the malfunction is
occurring
in the passenger inflator module circuitry.
4. This test check's for a short from the SRS COIL to
ground.
DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a poor
connection at DERM terminals
"A3" and "A4", dual pole
arming sensor terminals "2", "4", "5" or"7",water intrusion
in any discriminating sensor, an open in CKT 1810 or
CKT 1815, ora short to ground in CKT's 1810,1815, 1816,
1817, 1818,
1819, 1820, 1821, 1822, 1824, 1825, 1836.
Refer to DTC 25 diagnose a possible short to B+. When
the malfunction occurs during
an ignition cycle DTC 24
will set. If the malfunction is present at the beginning of
the next ignition
cycle DTC 25 will set and DTC 24 will be
moved to a history
file.
SAS·1 JOINT CONNEC'TlON ,, .
PASS SIDE HIGH PASS SIDE LOW
SRS INDICATOR

9J-62 Supplemental Restraint System
DTC 24 (PAGE 2 OF 3)
INITIATOR CIRCUIT VOLTAGE LOW
CIRCUIT DESCRIPTION
During normal, non-deployment operation of the SRS,
a small amount of current flows through both the driver
and
passenger deployment loops. The diagnostic
resistors within the dual pole arming sensor and the
discriminating sensors
along with the resistance of the
inflator modules cause voltage drops within the
deployment loops. The DERM monitors the voltage at
"Driver
Side Low" terminal "88" and "Passenger Side
Low" terminal "87"
to detect shorts or opens within the
driver deployment
loop. When the measured voltage at
terminal "88" or "87" is below a specified percentage of
its respective Driver 36 VLR power
supply voltage for
500 milliseconds DTC 24 is set.
DTC WILL SET WHEN
The voltage measured at "Driver Side Low'' terminal "88"
is below a specified percentage of "Driver 36 VLR" or
when the
voltage measured at "Passenger Side Low"
terminal "87" is below a specified percentage of
"Passenger 36 VLR" for 500 milliseconds. This test is run
during the "Continuous Monitoring" test.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic
trouble code.
""
DTC WILL CLEAR WHEN
The voltage measured at "Driver Side Low" terminal "88"
is within a specified percentage of "Driver 36 VLR" and
the
voltage measured at "Passenger Side Low" terminal
"87"
is within a specified percentage of "Passenger 36
VLR" for 500 milliseconds.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
10. This test checks for a short from the low side of the
driver deployment
loop to ground.
11. This test checks for a partial short across the
diagnostic resistor in the forward discriminating
sensor.
12.
This test checks for a partial short across the
diagnostic resistor in the passenger compartment
discriminating sensor.
13. This test checks for a short from the discriminating
sensor interconnect circuit to ground.
14. This test checks for a short from the
low side of the
driver deployment
loop to ground.
DIAGNOSTIC AIDS
Refer to DTC 24(Page 1 of 3).
SRS-1 JOINT CONNECTION 1 10 180& IGNITION 1 IGNITION 1 DRIVER SOURCE SENSE DRIVER 36VLR PASS. 38VLR PASS. SOURCE SENSE
AEOUNDAT INotCATOR GROUND
PASS SlOE HIGH PASS SIDE LOW
SPARE/LPS
SERIAL DATA
SRS INDICATOR

9J-64 Supplemental Restraint System

DTC 24 {PAGE 3 OF 3) \
INITIATOR CIRCUIT VOLTAGE LOW
CIRCUIT DESCRIPTION
During normal, non-deployment operation of the SRS,
a small amount of current flows through both the driver
and passenger deployment loops. The diagnostic
resistors within the dual pole arming sensor and the
discriminating sensors along with the resistance of the
inflator modules cause voltage drops within the
deployment loops. The DERM monitors the voltage at
"Driver Side Low" terminal "88" and "Passenger Side
Low"
terminal "87" to detect shorts or opens within the
driver deployment loop. When the measured voltage at
terminal
"88" or "87" is below a specified percentage of
its respective Driver 36 VLR for
500 milliseconds DTC 24
is set.
DTC WILL SET WHEN
The voltage measured at "Driver Side Low'' terminal "88"
is below a specified percentage of "Driver 36 VLR" or
when the voltage measured at "Passenger
Side Low"
terminal "87" is below a specified percentage of
"Passenger 36 VLR" for 500 milliseconds. This test is run
during the "Continuous Monitoring" test.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic trouble code.
DTC WILL CLEAR WHEN
The voltage measured at "Driver Side Low" terminal "88"
is within a specified percentage of "Driver 36 VLR" and
the voltage measured at "Passenger
Side Low" terminal
"87" is within a specified percentage of "Passenger 36
VLR" for 500 milliseconds.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
22. This test determines whether the malfunction is a
short from the high side of the passenger
deployment loop to ground. ·
23This test determines whether the malfunction is a
short from the high side of the Driver deployment
loop to ground.
24. This test checks for an open in the driver deployment
loop diagnostic resistor
of the dual pole arming
sensor.
25. This
test checks for an open in the passenger
deployment for an open in the passenger
deployment loop diagnostic resistor of the dual pole
arming sensor.
26. This test checks for high resistance in the "Driver 36
VLR" circuit.
27.
This test checks for high resistance in the
"Passenger 36 VLR" circuit.
28.
This test checks for high side of the driver
deployment loop.
29. This test checks for
an open in the high side of the
passenger deployment loop.
DIAGNOSTIC AIDS
Refer to DTC 24(Page 1 of 3).

9J-66 Supplemental Restr.aint System
DTC 25 (PAGE 1 OF 2)
INITIATOR CIRCUIT SHORT TO IGNITION
CIRCUIT DESCRIPTION
During the "Initiator Assembly Resistance Test" the
DERM grounds the
"Driver Side Low" terminal "BB" and
measures the voltage at "Driver Side Low" and
"Passenger Side Low." The DERM then grounds
"Passenger Side Low" terminal "B7" and again measures
the
voltage at "Driver Side Low" and "Passenger Side
Low."
For a properly operating circuit the voltage
measures the voltage measurements during each of
these tests
will be below a specified value. When the
voltages measured at both "Driver Side Low" and
"Passenger
Side Low'' are above a specified value during
both tests
DTC 25 is set.
DTC WILL SET WHEN
The voltages measured at both "Driver Side Low" and
"Passenger
Side Low" are above a specified value while
the DERM attempts to ground each of these terminals.
This test is run during the
"Initiator Assembly Resistance
Test" and the "1 0 Minute Loop Test" when: 1) "higher
priority
faults" are detected during ''Turn-ON", 2) No
"higher priority
faults" are detected during "continuous
Monitoring" for one second, 3) No
"Crank" signal present,
4)
"Ignition 1" voltage is above a specified value.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic
trouble code.
DTC WILL CLEAR WHEN
The voltages measured at either "Driver Side Low" or
"Passenger
Side Low" is below a specified value while
the DERM ground either of these terminals.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
2. This test determines whether the malfunction is
occurring
in the steering column circuitry.
3. This test determines whether the malfunction is
occurring
in the passenger inflator module circuitry.
4. This test for a short from the SRS COIL to +B.
DIAGNOSTIC AIDS
Refer to DTC 25(Page 2 of 2).
IGNmON 1 IGNITION 1 DRIVER SOURCE SENSE
~ -
DRIVER 38VLR PASS. 38VLR PASS. SOURCE SENSE 1DA 1&14 111011 D
REDUNDAT INDICATOR GROUND
PASS SIDE HIGH
PASS SIDE LOW
SPARE/l.PS DRIVER SEAT BelT
SERIAL DATA
SRS INDICATOR