OPEL FRONTERA 1998 Workshop Manual

RESTRAINT CONTROL SYSTEM 9J1–4
System Schematic
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SRS Diagnostic System Check
The diagnostic procedures used in this section are
designed to find and repair SRS malfunctions. To get the
best results, it is important to use the diagnostic charts
and follow the sequence listed below:
A. Perform the “SRS Diagnostic System Check.”
The “SRS Diagnostic System Check” must be the
starting point of any SRS diagnostics. The “SRS
Diagnostic System Check” checks for proper “AIR
BAG” warning lamp operation, the ability of the SDM
to communicate through the “Serial Data” line and
whether SRS diagnostic trouble codes exist.
B. Refer to the proper diagnostic chart as directed by the
“SRS Diagnostic System Check.”
The “SRS Diagnostic System Check” will lead you to
the correct chart to diagnose any SRS malfunctions.
Bypassing these procedures may result in extended
diagnostic time, incorrect diagnosis and incorrect
parts replacement.
C. Repeat the “SRS Diagnostic System Check” after any
repair or diagnostic procedures have been
preformed.
Performing the “SRS Diagnostic System Check” after
all repair or diagnostic procedures will ensure that the
repair has been made correctly and that no other
malfunctions exist
Circuit Description
When the ignition switch is first turned “ON”, “Ignition 1”
voltage is applied from the “C–21” fuse to the SDM at the
“Ignition 1” input terminals “12”. The SDM responds by
flashing the “AIR BAG” warning lamp turn on 3.5 seconds,
while performing tests on the SRS.
Notes On System Check Chart:
1. The “AIR BAG” warning lamp should turn on 3.5
seconds after ignition is first turned “ON”.
2. After the “AIR BAG” warning lamp turn on 3.5
seconds, it should turn “OFF”
3. This test checks for the proper operation of the
“Serial Data” line. This test will also determine
whether history diagnostic trouble codes are stored
and, if so, identify them.
4. Improper operation of the “AIR BAG” warning lamp
is indicated. This test differentiates a warning lamp
stays “ON” condition from a warning lamp does not
come “ON” condition.
5. This test checks for proper operation of the “Serial
Data” line. This test will also identify the stored
diagnostic trouble codes and whether they are
current or history.
Diagnostic Aids:
The order in which diagnostic trouble codes are
diagnosed is very important. Failure to diagnose the

9J1–5
RESTRAINT CONTROL SYSTEM
diagnostic trouble codes in the order specified may result in extended diagnostic time, incorrect diagnosis and
incorrect parts replacement.
SRS Diagnostic System Check
StepActionYe sNo
1Note the “Air Bag” warning lamp as ignition switch is turned “ON.”
Does the “AIR BAG” warning lamp turn on 3.5 seconds?
Go to Step 2Go to Step 3
2Note the “AIR BAG” warning lamp after it turn on 3.5 seconds.
Does the “AIR BAG” warning lamp go “OFF”?
Go to Step 4Go to Step 5
3Note the “AIR BAG” warning lamp as ignition switch is turned
“ON”.
Does the “AIR BAG” warning lamp come “ON” steady?
Go to Chart BGo to Chart C
41. Note the “AIR BAG” warning lamp as that ignition switch is
turned “ON.”
Ignition switch “OFF.”
2. Connect a scan tool to data link connector.
3. Follow direction given in the scan tool instruction manual.
Ignition switch “ON.”
4. Request the SRS diagnostic trouble code display, recode all
history diagnostic trouble code(s). specify as such, on repair
order
Is (are) diagnostic trouble code(s) displayed?Ignition switch
“OFF”
When DTC 71 is
set, go to DTC 71
Chart
For all other
history codes
refer to
“Diagnostic Aids”
For that specific
DTC
A history DTC
indicates the
malfunction has
been repaired or
is intermittent
SRS is functional
and free of
malfuncitons, no
further diagnosis
is required
If scan tool
indicated “NO
DATA
RECEIVED,”
refer to chassis
electrical section8
51. Ignition switch “OFF.”
2. Connect a scan tool to data link connector.
3. Follow directions as given in the scan tool instruction manual.
4. Ignition switch “ON.”
5. Request the SRS diagnostic trouble code display, Recode all
diagnostic trouble code(s), specifying as current or history on
repair order.
Is (are) diagnostic trouble code (s) displayed?Ignition switch
“OFF”
When DTC 53 is
set, go to DTC 53
chart
When DTC 51 is
set, go to DTC 51
chart
When DTC 19 is
set, go to DTC 19
chart
When DTC 25 is
set, go to DTC 25
chart
Diagnose
remaining current
DTCs from
lowest to highest
When only history
DTCs exist, refer
to “Diagnostics
Aids” for that
specific DTC
A history DTC
indicates the
malfunction has
been repaired or
is intermittent
If scan tool
indicates “No
Data Received,”
refer to chassis
electrical section8

RESTRAINT CONTROL SYSTEM 9J1–6
Chart A SDM Integrity Check
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Circuit Description:
When the SDM recognizes “Ignition 1” voltage, applied to
terminals “12”, is greater than 9 volts, the “AIR BAG”
warning lamp is turned on 3.5 seconds to verify operation.
At this time the SDM performs “Turn–ON” tests followed
by “Continuous Monitoring” tests. When a malfunction is
detected, the SDM sets a current diagnostic trouble code
and illuminates the “AIR BAG” warning lamp. The SDM
will clear current diagnostic trouble codes and move them
to a history file when the malfunction is no longer detected
and/or the ignition switch is cycled, except for DTCs 19,
25, 51, 53 and 71. DTC 71 can only be cleared using a
scan tool “Clear Codes” command. If DTCs 51, 53 are not
indicated then DTC 71 is not existing. DTCs 51, 53 and 71
can not be cleared after a “Clear Codes” command is
issued.
Chart Test Description:
Number(s) below refer to step number(s) on the
diagnostic chart:
1. This test confirms a current malfunction. If no
current malfunction is occurring (history DTC set)
the “Diagnostic Aids” for the appropriate diagnostic
trouble code should be referenced. The SDM
should not be replaced for a history diagnostic
trouble code.
2. This test checks for a malfunction introduced into the
SRS during the diagnostic process. It is extremely
unlikely that a malfunctioning SDM would cause a
new malfunction to occur during the diagnostic
process.
3. When all circuitry outside the SDM has been found
to operate properly, as indicated by the appropriate
diagnostic chart, then and only then should the SDM
be replaced.

9J1–7
RESTRAINT CONTROL SYSTEM
Chart A SDM Integrity Check
WARNING: DURING SERVICE PROCEDURES. BE VERY CAREFUL WHEN HANDLING A SENSING AND
DIAGNOSTIC MODULE (SDM). NEVER STRIKE OR JAR THE SDM. NEVER POWER UP THE SRS WHEN THE
S D M I S N O T R I G I D LY AT TA C H E D T O T H E V E H I C L E . A L L S D M A N D M O U N T ING BRACKET FASTENERS MUST
BE CAREFULLY TORQUED AND THE ARROW MUST BE POINTING TOWARD THE FRONT OF THE VEHICLE
TO ENSURE PROPER OPERATION OF THE SRS. THE SDM COULD BE ACTIVATED WHEN POWERED WHILE
NOT RIGIDLY ATTACHED TO THE VEHICLE WHICH COULD CAUSE DEPLOYMENT AND RESULT IN
PERSONAL INJURY.
Step
ActionYe sNo
11. This chart assumes that the “SRS Diagnostic System Check”
and either a symptom chart or a diagnostic trouble code chart
diagnosis have been performed. When all circuitry outside the
SDM has been found to operate properly, as indicated by the
appropriate diagnostic chart, and the symptom or DTC
remains current, the following
2. Diagnostic procedures must be performed to verify the need
for SDM replacement.
3. Ignition switch “OFF”.
4. Reconnect all SRS components, ensure all components are
properly mounted.
5. Ensure the ignition switch has been “OFF” for at least 15
seconds.
6. Note “AIR BAG” warning lamp as ignition switch is turned
“ON.”
Does warning lamp turn on 3.5 seconds then go “OFF”?
The symptom or
DTC is no longer
occurring
Clear SRS
diagnostic trouble
codes
Repeat “SRS
Diagnostic
System Check”
Go to Step 2
2Using a scan tool request diagnostic trouble code display
Is the same symptom or DTC occurring as was when the “SRS
Diagnostic System Check ” was first performed?
Go to Step 3
Ignition switch
“OFF”
Go to the
appropriate chart
for the indicated
malfunction
31. Clear “SRS Diagnostic Trouble Codes”.
2. Ignition switch “OFF” for at least two minutes.
3. Note “AIR BAG” warning lamp as ignition switch is turned
“ON.”
Does warning lamp turn on 3.5 seconds then go “OFF”?SRS is functional
and free of
malfunctions
No further
diagnosis is
required
Go to Step 4
Ignition switch
“OFF”
Replace SDM
Go to Step 4
4Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished?Repeat the “SRS
Diagnostic
System Check”
Go to Step 4

RESTRAINT CONTROL SYSTEM 9J1–8
Chart B “AIR BAG” Warning Lamp Comes “ON” Steady
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Circuit Description:
When the ignition switch is first turned “ON”, “Ignition 1”
voltage is applied from the “C–10” fuse to “AIR BAG”,
warning lamp which is connected to “SRS Warning
Lamp”, terminal “7”. The “C–21” fuses apply system
voltage to the “Ignition 1” inputs, terminals “12”. The SDM
responds by turning on the “AIR BAG” warning lamp 3.5
seconds. If “Ignition 1” is less than 9 volts, the “AIR BAG”
warning lamp will come “ON” solid with no DTCs set.
Chart Test Description:
Number(s) below refer to step number(s) on the
diagnostic chart.
2. This test checks for an open in the “Ignition 1” circuit
to the SDM.
3. This test checks for the voltage of “IGNITION 1”.
4. This test determines whether the malfunction is a
short to ground in IB04–WHT/RED.

9J1–9
RESTRAINT CONTROL SYSTEM
Chart B “AIR BAG” warning lamp comes “ON” Steady
StepActionYe sNo
11. 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 2Go to Step 3
21. Ignition switch “OFF”.
2. Inspect SDM harness connector connection to SDM.
Is it securely connected to the SDM?
Ignition switch
“OFF”
Replace SDM
Go to Step 5
Connect SDM
securely to
de–activate
shorting clip in
SDM harness
connector
Go to Step 5
3Using scan tool, request SRS data list.
Is “ignition” less than 9 volts?
Go to Step 4
Ignition switch
“OFF”
Replace SDM
Go to Step 5
41. Ignition switch “OFF.”
2. Disconnect SRS coil and passenger air bag assemblies.
yellow 2–pin connector located at base of steering column and
behind the glove box assembly.
Disconnect SDM.
3. Disconnect the connector of “SRS Warning Lamp” of
instrument cluster.
4. Measure resistance from SDM harness connector terminal “7”
to ground “6”.
Does 5–8840–0285–0 display “OL” (Infinite)?
Go to Chart A
Replace SRS
harness
Go to Step 5
5Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished?Repeat the “SRS
Diagnostic
System Check”
Go to Step 5

RESTRAINT CONTROL SYSTEM 9J1–10
Chart C “AIR BAG” Warning Lamp Does Not Come “ON” Steady
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Circuit Description:
When the ignition switch is first turned “ON”, “Ignition 1”
voltage is applied from the “C–10” fuse to the “AIR BAG”
warning lamp which is connected to “SRS Warning
Lamp”, terminal “7”. The “C–21” fuse apply system
voltage to the “Ignition 1” inputs, terminals “12”. The SDM
responds by turning on the “AIR BAG” warning lamp 3.5
seconds. 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 SDM
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 IB04–WHT/RED circuit and
checks for a short in the IB04–WHT/RED circuit to
B+.
8. This test checks for a short from the SDM warning
lamppower feed circuit to ground.
9. This test determines whether the short to ground is
due to a short in the wiring.

9J1–11
RESTRAINT CONTROL SYSTEM
Chart C “AIR BAG” Warning Lamp Does Not Come “ON” Steady
StepActionYe sNo
11. 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 “C–10” fuse (meter) to the “AIR BAG”
warning lamp.
Is fuse good?
Go to Step 2Go to Step 7
21. Ignition switch “OFF.”
2. Disconnect SRS coil and passenger air bag assemblies.
Yellow 2–pin connector located at base of steering column and
behind the glove box assembly.
3. Disconnect SDM.
4. Ignition switch “ON.”
5. Measure voltage on SDM harness connector from terminal “7”
to terminal “6” (ground).
Is system voltage present on terminal “7”?
Go to Step 4Go to Step 3
31. Ignition switch “OFF.”
2. Remove instrument meter cluster.
3. Check for proper connection to instrument cluster at
IB04–WHT/RED terminal.
4. If ok, then remove and inspect “AIR BAG” bulb.
Is bulb good?
Go to Step 5
Replace bulb
Go to Step 6
41. Ignition switch “OFF.”
2. Disconnect instrument meter cluster harness connector.
3. Ignition switch “ON.”
4. Measure voltage on SDM harness connector from terminal “7”
to terminal “6” (GROUND).
Is voltage 1 volt or less?
Go to Chart A
Replace SRS
harness
Go to Step 6
51. Install bulb.
2. Measure resistance from instrument meter cluster harness
connector IB04–WHT/RED terminal to SDM 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
6Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished?Repeat the “SRS
Diagnostic
System Check”
Go to Step 6
7Perform chart C.
Was this step finished?
Go to Step 8Go to Step 1
81. Replace “C–10” fuse.
2. Ignition switch “ON” wait 10 Seconds then ignition switch “Off.”
3. Remove and inspect “C–10” fuse.
Is fuse good?
Install “C–10”
fuse
Go to Step 10
Go to Step 9

RESTRAINT CONTROL SYSTEM 9J1–12
Chart C “AIR BAG” Warning Lamp Does Not Come “ON” Steady (Cont’d)
StepNo Ye s Action
91. Disconnect SRS coil and passenger air bag assemblies.
Yellow 2–pin connectors located at base of steering column
and behind the glove box assembly.
2. Disconnect SDM.
3. Replace “C–10” fuse.
4. Ignition switch “ON” wait 10 seconds.
5. Ignition switch “OFF”.
6. Remove and inspection “C–10” fuse.
Is fuse good?
Install“C–10” fuse
Go to Chart A
Replace SRS
harness
Replace “C–10”
fuse
Go to Step 10
10Reconnect all SRS components, ensure all components are
properly mounted.
Was this step finished?Repeat the “SRS
Diagnostic
System Check”
Go to Step 10

9J1–13
RESTRAINT CONTROL SYSTEM
DTC 15 Passenger Deployment Loop Resistance High
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Circuit Description:
When the ignition switch is turned “ON”, the SDM 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
SDM then proceeds with the “Resistance Measurement
Test”. “Passenger Bag Low” terminal “16” is grounded
through a resister and the passenger current source
connected to “Passenger Bag High” terminal “15” allows a
known amount of current to flow. By monitoring the
voltage difference between “Passenger Bag High” and
“Passenger Bag Low” 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 “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:
SDM turns “ON” the “AIR BAG” warning lamp and sets a
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. 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 checks for proper contact and/or corrosion
of the yellow 2–pin connector terminals.
5. The test checks for a malfunctioning passenger air
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”, SDM terminal “15” and
“16”, or a poor wire to terminal connection in
IB07–YEL/GRN and IB08–YEL/RED. This test for this
diagnostic trouble code is only run while the “AIR BAG”