Daewoo Nubira. Manual - part 215

8B – 6

I

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)

DAEWOO V–121 BL4

COMPONENT LOCATOR

SIR COMPONENT AND WIRING LOCATION VIEW

1. Clock 

Spring

2. Connector 

C208

3. Passenger 

Airbag

4.  Sensing and Diagnostic Module (SDM)
5.  Data Link Connector (DLC)
6. Driver 

Airbag

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)  8B – 7

DAEWOO V–121 BL4

DIAGNOSIS

DIAGNOSTIC TROUBLE CODES
(DTC)

The supplemental inflatable restraint (SIR) Diagnostic
System Check must always be the starting point for any
SIR system diagnosis. The Diagnostic System Check re-
veals diagnostic trouble codes (DTCs) through the use of
a scan tool, and checks for proper AIRBAG warning indi-
cator operation.

Two types of diagnostic trouble codes may be recorded:

1.  Current diagnostic trouble codes represent mal-

functions that are presently being detected. Current
DTCs are stored in random access memory.

2.  History DTC represent all malfunctions that were

detected since the last time that history memory
was cleared. History DTCs are stored in the elec-
tronically erasable programmable read only
memory (EEPROM).

SCAN TOOL DIAGNOSTICS

A scan tool can read serial data from terminal 9 of the data
link connector (DLC). A specific replaceable cartridge
must be attached to the scan tool before the scan tool can
communicate with the sensing and diagnostic module
(SDM) for the purpose of diagnostics. The scan tool is
used to read diagnostic trouble codes (DTCs), and to clear
some DTCs after a repair is completed. By design, certain
codes cannot be cleared. To use the scan tool, turn the
ignition OFF, connect the scan tool to the DLC, and turn
the ignition ON. Follow the instructions in the scan tool
manual. The SDM sends serial data from terminal 5 of the
SDM to terminal 9 of the DLC.

USE OF SPECIAL TOOLS

A scan tool is used to read and clear diagnostic trouble
codes (DTCs). A connector adapter kit provides jumper
wires and terminal adapters to make it easier to test small
terminals. In diagnostic testing, a load tool is used as a
substitute for the airbag modules. A wiring harness check-
er and a deployment tool are under development, and ser-
vice bulletins will be issued if these tools become opera-
tional.

SIR DIAGNOSTIC SYSTEM CHECK

Notice : If the vehicle interior has been exposed to exten-
sive water intrusion such as water leaks, driving through
high water, flooding, or other causes, the sensing and
diagnostic module (SDM) and the SDM connector may
need to be replaced. With the ignition OFF, inspect the
area around the SDM, including the carpet. If any signifi-
cant soaking or evidence of previous soaking is detected,
the water must be removed, the water damage repaired,
and the SDM and SDM connector must be replaced. Be-

fore attempting any of these repairs, the supplemental in-
flatable restraint (SIR) system must be disabled. Refer to
 ”Disabling the SIR System”  and”Sensing and Diagnostic
Module (SDM)”  in this section for instructions on how to
disable the SIR system and replace the SDM.

The diagnostic procedures used in this section are de-
signed to find and repair SIR system conditions. To get the
best results, it is important to use the diagnostic charts and
follow the sequence listed below.

1.  Perform the SIR Diagnostic System Check. The

SIR Diagnostic System Check must be the starting
point of any SIR diagnostics. The SIR Diagnostic
System Check reveals diagnostic trouble codes
(DTCs) through the use of a scan tool, and checks
for proper AIRBAG indicator operation.

2.  Refer to the proper diagnostic chart as directed by

the SIR Diagnostic System Check. The SIR Diag-
nostic System Check will lead to the correct chart
to diagnose any SIR system malfunctions. Bypass-
ing these procedures may result in extended diag-
nostic time, incorrect diagnosis, and incorrect parts
replacement.

3.  Repeat the SIR Diagnostic System Check after any

repair or diagnostic procedures have been per-
formed. Performing the SIR 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 is first turned ON, Ignition 1 voltage is
applied from the airbag fuse to the SDM at input terminal
10. The SDM responds by flashing the AIRBAG indicator
seven times and then turning it off while the SDM performs
tests on the SIR system.

Diagnostic Aids

The order in which DTCs are diagnosed is very important.
Failure to diagnose the DTCs in the order specified may
result in extended diagnostic time, incorrect diagnosis and
incorrect parts replacement.

Test Description

The number(s) below refer to step(s) on the diagnostic
table.

3.

This test will identify the stored DTCs and whether
they are current or history. A history DTC indicates
that the malfunction has been repaired or is inter-
mittent.

6.

This test differentiates between an indicator that will
not come on and an indicator that stays on when it
should be off.

7.

See the first caution below.

9.

See the cautions below.

10. This test will determine whether history DTCs are

stored and will identify them.

11. A history DTC indicates that the malfunction has

been repaired or is intermittent.

8B – 8

I

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)

DAEWOO V–121 BL4

SIR Diagnostic System Check

CAUTION :  The SDM can maintain sufficient voltage
to deploy the airbags for 10 minutes after the ignition
is OFF and the fuse has been removed. If the airbags
are not disconnected, service cannot begin until 10
minutes have passed after disconnecting power to
the SDM.

CAUTION :  During service procedures, be very care-
ful when handling the SDM. Never strike or jar the

SDM. Never power the SIR system when the SDM is
not rigidly attached to the vehicle. All SDM mounting
bolts must be carefully tightened, and the SDM arrow
must be pointing toward the front of the vehicle to en-
sure proper operation of the SIR system. The SDM
could be activated if it is powered when it is not rigidly
attached to the vehicle, resulting in unexpected de-
ployment and possible injury.

Step

Action

Value(s)

Yes

No

1

1.  Turn the ignition switch to ON.
2.  Observe the AIRBAG indicator as the ignition

is being turned ON.

Does the indicator flash seven times?

Go to Step 2

Go to Step 6

2

Observe the AIRBAG indicator after it flashed seven
times.
Does the indicator turn OFF?

Go to Step 10

Go to Step 3

3

1.  Turn the ignition to LOCK and remove the key.
2.  Connect the scan tool to the Data Link Con-

nector (DLC). Follow the directions given in the
scan tool manual.

3.  Turn the ignition ON.
4.  Request the supplemental inflatable restraint

SIR) diagnostic trouble code (DTC) display on
the scan tool.

5.  Record all DTCs, indicating each as either a

current or a history DTC.

Are only history DTCs shown?

Refer to the

DTC chart for

any DTC that

was set, and

refer to the

Diagnostic Aids

for that specific

DTC

Go to Step 4

4

Check the recorded DTCs.
Are current DTCs 18, 24, or 51 set?

Go to the DTC
chart indicated

by any of these

three codes

Go to Step 5

5

Check the recorded DTCs.
Are there any other current DTCs shown?

Diagnose the

remaining cur-

rent DTCs from

lowest number

to highest

Refer to the

DTC chart for

any history

DTC that was

set, and refer

to  ”Diagnostic

Aids”  for that

specific DTC

6

Observe the AIRBAG indicator after the ignition has
been turned ON.
Does the AIRBAG indicator stay on?

Go to ”AIRBAG

Warning Lamp

Stays on with

Ignition Switch

ON”

Go to Step 7

7

1.  Turn the ignition to LOCK and remove the key.
2.  Temporarily disconnect the passenger airbag

and the yellow clock spring connector on the
steering column.

3.  Check the AIRBAG indicator bulb and circuit.

Are the bulb and the bulb circuit in good condition?

Go to Step 9

Go to Step 8

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)  8B – 9

DAEWOO V–121 BL4

Step

No

Yes

Value(s)

Action

8

1.  Replace the bulb or repair the bulb circuit.
2.  Connect all SIR system components, and en-

sure that all components are properly mounted.

Is the repair complete?

Go to Step 1

9

1.  Turn the ignition to LOCK and remove the key.
2.  Disconnect the passenger airbag and the yel-

low clock spring connector on the steering col-
umn.

3.  Replace the SDM. The arrow must be pointing

toward the front of the vehicle.

4.  Reconnect all SIR system components, and

ensure that all components are properly
mounted.

Is the repair complete?

Go to Step 1

10

1.  Turn the ignition to LOCK and remove the key.
2.  Connect the scan tool to the data link connec-

tor (DLC). Follow the directions given in the
scan tool manual.

3.  Turn the ignition to ON.
4.  Request the SIR DTC display on the scan tool.
5.  Record all history DTCs.

Are any SIR DTCs displayed?

Go to Step 11

System OK

11

Turn the ignition to OFF.
Is DTC 71 set?

Go to  ”DTC 71

Internal SDM

Failure” 

Refer to the

DTC chart for

any history

DTC that was

set, and refer

to  ”Diagnostic

Aids”  for that

specific DTC

SENSING AND DIAGNOSTIC

MODULE (SDM) INTEGRITY CHECK

The following diagnostic chart must be followed when all
circuitry outside the sensing and diagnostic module SDM)
has been found to operate properly, as indicated by follow-
ing the appropriate diagnostic trouble code DTC) chart or
symptom chart. This chart verifies the need for SDM re-
placement.

Circuit Description

When the SDM recognizes Ignition 1 voltage greater than
8.2 volts at terminal 10 of the SDM, the AIRBAG indicator
is flashed seven times to verify operation. At this time the
SDM performs turn–on tests followed by resistance mea-
surement tests and continuous monitoring tests. When a
malfunction is detected, the SDM sets a current DTC and
illuminates the AIRBAG indicator. When the malfunction
is no longer detected and/or the ignition switch is cycled,
the SDM will clear current DTCs and move them to a histo-

ry file, except for DTCs 18, 24, 51, 53, and sometimes 71.
DTCs 18, 24, 51, and 53 will not clear using a scan tool be-
cause these codes require replacement of the SDM. The
SDM must be replaced only after the malfunction that set
the DTC has been repaired.

Test Description

The number(s) below refer to step(s) on the diagnostic
table.

1.

This test confirms a current malfunction. If no cur-
rent malfunction is occurring, (history DTC set),
refer to ”Diagnostic Aids” for the appropriate DTC.
The SDM should not be replaced for a history DTC
except when directed.

2.

This test checks for a malfunction introduced into
the supplemental inflatable restraint (SIR) system
during the diagnostic process. It is extremely un-
likely that a malfunctioning SDM would cause a
new malfunction to occur during the diagnostic pro-
cess.

4.

See the cautions below.