1995 ISUZU TROOPER Workshop Manual

STEP
1 WAS THE "SRS PERFORMED?
Supplemental Restraint System 9J-1 05
\: DTC 71 AND/OR 75
INTERNAL DERM FAULT
ACTION
YES
DIAGNOSTIC SYSTEM CHECK"
REPLACE DERM.
REPEAT THE "SRS
DIAGNOSTIC SYSTEM CHECK." NO
GO TO
THE "SRS
DIAGNOSTIC SYSTEM CHECK."

9J-106 Supplemental Restraint System
DTC81
DRIVER IGNITION DIODE OPEN
CIRCUIT DESCRIPTION
During the "Turn-ON" tests, performed at the beginning
of each ignition
cycle, the DERM delays the charging of
the "Driver
3S VLR" and "Passenger 3S VLR" power
supplies. While the delay is active the DERM measures
the
voltage at the "Driver 3S VLR" terminal "A3", "Driver
Source
Sense" terminal "AS", and "Passenger Source
Sense" terminal "AS". When the voltage measured at the
two
"3S VLR" power supplies indicates they are in a
discharged state, the
voltage measured at "Passenger
Source
Sense" is within a specified range of "Ignition 1"
voltage
measured at "Driver Source Sense" is a specified
amount
below "Ignition 1" voltage DTC 81 is set.
DTC WILL SET WHEN
With both "3S VLR" power supplies in a discharged state,
the DERM detects
"Ignition 1" voltage at "Passenger
Source
Sense" terminal "AS" while simultaneously the
DERM detects
"Ignition 1" voltage at "Driver Source
Sense" terminal "AS". This test is run once each ignition
cycle during the "Turn-ON" tests while the "3S VLR
Delay"
is active.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic
trouble code.
DTC CHART TEST DESCRIPTION
Number(s) below refer to step number(s) on the
diagnostic chart.
2. This test checks for a short from the "Driver Source
Sense" circuit to the "Passenger 3S VLR" circuit.
3. This test checks for a short from the "Driver Source
Sense"circuit to the "Driver
3S VLR" circuit.
4. This test determines whether the malfunction is due
to open within the
dual pole arming sensor.
DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a short
between
CKT 1811 CKTIB12, a short between CKT 1811
and CKT 1813 or an open inside the dual pole arming
sensor. The test for this diagnostic
trouble code is only
run while the check. When a scan tool "Clear Codes"
command is issued and the malfunction is still present,
the
DTC will not reappear until the ignition switch is
turned
"OFF" for at least two minutes with the entire SRS
connected and then the ignition switch is turned "ON."
SRS-1 FUSE JOINT CONNECTION TOS~~~:?N -_;:,;SR-" !
IGNmON ~-=-------"T"---""'1107<----SWrTCH SRS C-22 10A 1111
1112 DRIVER 36VLR PASS.36VLR PASS. SOURCE SENSE
REOUNOAT INDICATOR GROUND
PASS SIDE HIGH
PASS SIDE LOW
SERIAL DATA
SRS INDICATOR
•

Supplemental Restraint System 9J-1 07
DTC81
DRIVER IGNITION DIODE OPEN
STEP
ACTION
YES NO
1 WAS THE "SRS
DIAGNOSTIC
SYSTEM CHECK" GOTOSTEP2. GO TO THE "SRS
PERFORMED? DIAGNOSTIC
SYSTEM CHECK."
2
WHEN MEASUREMENTS ARE REQUESTED IN THIS CHART GOTOSTEP3. GO TO STEPS.
USE
J-39200 DVM WITH CORRECT TERMINAL ADAPTER
FROM J-35616-A. IGNITION SWITCH "OFF."
DISCONNECT DRIVER
AND PASSENGER INFLATOR
MODULES, YELLOW 2-WAY OR 4-WAY CONNECTORS
LOCATED AT THE TOP OF THE STEERING COLUMN AND BEHIND THE 1/P COMPARTMENT DOOR ASSEMBLY.
DISCONNECT DUAL POLE ARMING SENSOR.
MEASURE RESISTANCE ON DUAL POLE ARMING SENSOR
HARNESS CONNECTOR FROM TERMINAL "5" TO TERMINAL
"6".
DOES J-39200 DISPLAY "OL"(INFINITE)?
3 MEASURE RESISTANCE ON DUAL POLE ARMING SENSOR GOTOSTEP4. GO TO STEPS.
HARNESS CONNECTOR FROM TERMINAL "4" TO TERMINAL
"6".
DOES J-39200 DISPLAY "OL"(INFINITE}?
4 RECONNECT DUAL POLE ARMING SENSOR. GOTOSTEP6. IGNITION SWITCH
DISCONNECT
DERM. "OFF."
IGNITION SWITCH "ON." GO
TO CHART A.
MEASURE VOLTAGE FROM DERM HARNESS CONNECTOR
TERMINAL "AS" TO TERMINAL "A1"(GROUND).
IS VOLTAGE 1 VOLT OR LESS?
5 REPLACE SRS HARNESS. GOTOSTEP7.
6 IGNITION SWITCH "OFF." GOTOSTEP7.
REPLACE DUAL POLE ARMING SENSOR.
7 RECONNECT ALL SRS COMPONENTS,
ENSURE ALL GO TO THE "SRS DIAGNOSTIC SYSTEM
COMPONENTS
ARE PROPERLY MOUNTED. CHECK". CLEAR SRS DIAGNOSTIC TROUBLE CODES.
REPEAT THE "SRS DIAGNOSTIC SYSTEM CHECK."

9J-1 08 Supplemental Restraint System
DTC82
PASSENGER IGNITION DIODE OP N
CIRCUIT DESCRIPTION
During the "Turn-ON" tests, performed at the beginning
of each ignition
cycle, the DERM delays the charging of
the "Driver 36
VLR" and "Passenger 36 VLR" power
supplies.
While the delay is active the DERM measures
the voltage at the "Driver 36 VLR" terminal "A4",
"Passenger 36 VLR" terminal "A3", "Driver Source
Sense"
terminal "AS", and "Passenger Source Sense"
terminal "A6". When the voltage measured at the two "36
VLR"
power supplies indicates they are in a discharged
state, the voltage measured at "Driver
Source Sense" is
within a specified range of
"Ignition 1" voltage measured
at "Passenger
Source Sense" is a specified amount
below "Ignition 1" voltage DTC 82 is set.
DTC WILL SET WHEN
With both "36 VLR" power supplies in a discharged state,
the DERM detects
"Ignition 1" voltage at "Driver Source
Sense" terminal
"AS" while simultaneously the DERM
does not detect
"Ignition 1" voltage at "Passenger Source
Sense"
terminal "A6". This is run once each ignition cycle
during the
"Turn-ON" tests while the "36 VLR Delay" is
active.
ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets
a diagnostic trouble code.
DTC WILL CLEAR WHEN
With both "36 VLR" power supplies in a discharged state,
the voltages measured at "Driver
Source Sense"
'"'
terminal "AS" and "Passenger Source Sense" terminal
"A6" are simultaneously within a specified range of
"Ignition 1" voltage. When neither the failure nor clear
conditions are met, the state of the DTC from the
previous ignition cycle is used.
DTC CHART TEST DESCRIPTION
Number{s) below refer to step number{s) on the
diagnostic chart.
2. This test checks for a short from the "Passenger
Source Sense" circuit to the "Passenger 36 VLR"
circuit.
3. This test check for a short from the "Passenger
Source Sense" circuit to the "Driver 36 VLR" circuit.
4. This test determines whether the malfunction is due
to an open within the
dual pole arming sensor.
DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a short
between
CKT IB12 and CKT IB14, a short between CKT
IB13
and CKT IB14, or an open inside the dual pole
arming sensor. 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 ignition
switch is turned
"OFP for at least two minutes with the
entire
SRS connected and then the ignition switch is
turned
"ON."
SRS-1 JOINT CONNEcnoN . lG,J;~ON _ _.::FU::OS£'---.-r:--m_-SWITCH SRS C..z2 10A
•