ground DAEWOO LACETTI 2004 Service Repair Manual

8B – 82ISUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)
DAEWOO V–121 BL4
J3B18B07
18191 2
SDM Driver
Side Airbag
ModulePassenger
Side Airbag
Module
WHT/
YEL
BLK/
WHTPNK/
WHTBRN/
WHT BLKDK GRN/
YEL
RED/
YEL WHT/
DK BLU DK GRN/
DK BLU
6
G202
20
1 1
2425C301
16
45
17
Driver
Side Airbag
Sensor12
21
1 246
Passenger
Side Airbag
Sensor
DIAGNOSTIC TROUBLE CODE (DTC) 85
PASSENGER SIDE AIRBAG SENSOR LOOP IS SHORTED
TO GROUND
Circuit Description
When the ignition switch is turned to ON, the sensing and
diagnostic module(SDM) will perform turn–on test to diag-
nose critical malfunctions within SDM itself.
Upon passing these test ignition and deployment loop volt-
ages are measured to ensure that they are within their nor-mal voltage ranges. The SDM monitors the voltages at the
driver low and the passenger low to detect shorts to
ground or voltage in the deploy loops.
DTC 84 Will Set When
S The side airbag sensor wiring of passenger’s high
is shorted to ground.
S The side airbag sensor wiring of passenger’s low is
shorted to ground.

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR) 8B – 83
DAEWOO V–121 BL4
DTC 85
Passenger Side Airbag Sensor Loop Is Shorted To
Ground
CAUTION : The sensing and diagnostic module(SDM)
can maintain sufficient voltage to deploy the airbags
and pretensioners for 1 minute after the ignition is
OFF and the fuse has been removed. If the airbags
and pretensioners are not disconnected, do not be-
gin service until one minute has passed after discon-
necting power to SDM. Otherwise, injury could result.
CAUTION : During service procedure, be very careful
when handling the SDM. Never strike or jar the SDM.Never power the supplemental inflatable re-
straints(SIR) when the SDM is not rigidly attached to
the vehicle. All SDM mounting bolts must be carefully
tightened , and the arrow on the SDM must be point
toward the front of the vehicle to ensure proper op-
eration of the SIR. The SDM could be activated if it is
powered when it is not rigidly attached to the vehicle,
resulting in unexpected deployment and possible in-
jury.
Step
ActionValue(s)YesNo
11. Confirm the ignition switch ”OFF”.
2. Wait for a minute the SDM charger to be dis-
charged.
3. Visually check any damage for the passenger
side airbag sensor wiring and the connector.
Are the airbag wiring and connector damaged
OK?–Go to Step 3Go to Step 2
2Replace the airbag wiring and connect the connec-
tor.–––
3Check the resistance between the SDM and the
high, low terminal of passenger side airbag sensor
and the ground. Is the resistance 10KΩ?
10K ΩGo to Step 4Go to Step 6
41. Replace the SDM.
2. Confirm the ignition switch ”ON”.
3. Remove the DTC with scan tool.
4. Check the circuit. Is the DTC still exist?–Go to Step 5The system is
OK.
5Replace the passenger side airbag sensor.–––
6Replace the airbag wiring.–––

8B – 84ISUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)
DAEWOO V–121 BL4
J3B18B07
18191 2
SDM Driver
Side Airbag
ModulePassenger
Side Airbag
Module
WHT/
YEL
BLK/
WHTPNK/
WHTBRN/
WHT BLKDK GRN/
YEL
RED/
YEL WHT/
DK BLU DK GRN/
DK BLU
6
G202
20
1 1
2425C301
16
45
17
Driver
Side Airbag
Sensor12
21
1 246
Passenger
Side Airbag
Sensor
DIAGNOSTIC TROUBLE CODE (DTC) 86
PASSENGER SIDE AIRBAG SENSOR COMMUNICATION
ERROR
Circuit Description
When the ignition switch is turned to ON, the sensing and
diagnostic module(SDM) will perform turn–on test to diag-
nose critical malfunctions within SDM itself.
Upon passing these test ignition and deployment loop volt-ages are measured to ensure that they are within their nor-
mal voltage ranges. The SDM monitors the voltages at the
driver low and the passenger low to detect shorts to
ground or voltage in the deploy loops.
DTC 86 Will Set When
S a communication error occurs between the SDM
and the passenger side airbag sensor.

8B – 86ISUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)
DAEWOO V–121 BL4
J3B18B07
18191 2
SDM Driver
Side Airbag
ModulePassenger
Side Airbag
Module
WHT/
YEL
BLK/
WHTPNK/
WHTBRN/
WHT BLKDK GRN/
YEL
RED/
YEL WHT/
DK BLU DK GRN/
DK BLU
6
G202
20
1 1
2425C301
16
45
17
Driver
Side Airbag
Sensor12
21
1 246
Passenger
Side Airbag
Sensor
DIAGNOSTIC TROUBLE CODE (DTC) 87
PASSENGER SIDE AIRBAG SENSOR FAILURE
Circuit Description
When the ignition switch is turned to ON, the sensing and
diagnostic module(SDM) will perform turn–on test to diag-
nose critical malfunctions within SDM itself.
Upon passing these test ignition and deployment loop volt-ages are measured to ensure that they are within their nor-
mal voltage ranges. The SDM monitors the voltages at the
driver low and the passenger low to detect shorts to
ground or voltage in the deploy loops.
DTC 87 Will Set When
S The the passenger side airbag sensor is inopera-
tive.

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR) 8B – 97
DAEWOO V–121 BL4
AIRBAG MODULE DEPLOYMENT
(OUTSIDE OF VEHICLE)
If the vehicle is within the warranty period, contact the
Daewoo regional service manager for approval or
special instructions before deploying the airbag mod-
ules.
Deploy airbag modules in following situations :
S If the vehicle is to be strapped. Refer to”Airbag
Module Deployment(Inside of Vehicle” in this sec-
tion.
S If an airbag module is damaged during transit, stor-
age or service.
CAUTION : To avoid injury while deploying an air-
bag or a pretensioner outside the vehicle, ob-
serve the following precaution :
S Deploy the airbags only in an evacuated area. Ser-
vice personnel who must be present during the de-
ployment should be at least 10 meters(33 feet) in
front of the vehicle.
S Do not connect the voltage source until after having
completed all other preparations for the deployment
of airbags.
S Allow a deployed airbag module or pretensioner
cool for 30 minutes before handling.
S Wear gloves and eye protection during the disposal
procedure.
S If the deployment fails, disconnect the voltage
source and wait 5 minutes before approaching the
vehicle.
1. Position the airbag module face up, on flat ground
outdoors, at least 10 meters(33 feet) from the any
obstacles or people.
2. Place a vehicle battery at least 10 meters(33 feet)
away from the airbag module.
3. Deploy the airbag module.
4. Please follow detailed Airbag Module deployment
procedure as below.
5. Cut the yellow wires to the airbag module/preten-
sioner.
6. Strip 13mm(0.5 inch) of the insulation from the end
of the wires leading to the airbag module/preten-
sioner.
7. Use two additional wires, each at least 10 me-
ters(33 feet) long, to reach from the deployment
battery to the airbag module/pretensioner.
8. Strip 13mm(0.5 inch) of the insulation from the
ends of these two additional wires.
9. Twist the two wires together at one end.
10. Place the twisted ends of the two wires near the
deployment battery. Do not connect the wires to the
battery at this time.

SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR) 8B – 101
DAEWOO V–121 BL4
FRONT SEAT BELT
PRETENSIONERS
CAUTION : Tempering with seat belt pretensioner
creates the risk of an injury from unexpected deploy-
ment. Therefore, the driver airbag module should
never be disassembled.
The seat belt pretensioners(with load limiter for some ve-
hicles) are assembled with each front seat belt retractors
to retract the seat belt webbing when accounted frontal
collision. The seat belt pretensioners are controlled by
sensing and diagnostic module(SDM). The seat belt pre-
tensioner contains an igniter charge and a gas generator
to pull the seat belt webbing. The seat belt pretensioner
must be replaced after an accident that causes its activa-
tion.
The seat belt pretensioner also contains a shorting bar to
prevent current from travelling through the seat belt pre-
tensioner during servicing. The shorting bar is disengaged
when the connector is connected.
SENSING AND DIAGNOSTIC
MODULE (SDM)
CAUTION : During the service procedures, be careful
when handling the SDM. Never shake or jar the SDM.
Never apply power to SIR when the SDM is not rigidly
attached to the vehicle. All SDM mounting bolts and
grounding nuts must be fully tightened. Failure to fol-
low these precautions could cause deployment and
result in personal injury.
The SDM is located on the floor beneath the floor console
assembly. The SDM performs the following functions :
S Monitors the supplemental inflatable restraints(SIR)
electrical components and sets a diagnostic trouble
code(DTC) when malfunction is detected.
S Records any faults that are discovered.
S Displays SIR diagnostic trouble codes and system
status information when connected to a scan tool.
S Illuminates the airbag indicator to alert the driver to
any fault.S Provides a reserve power source to deploy the air-
bags and pretensioners if an accident has disabled
the normal power source.
S Monitors vehicle velocity changes to detect frontal
impacts, which are severe enough to warrant de-
ployment.
S Causes current to flow through the airbag modules
and pretensioner to cause deployment if a frontal
impact of sufficient force is detected.
The SDM contains no user–serviceable parts.
AIRBAG WARNING LAMP
The instrument cluster contains an airbag warning indica-
tor and sensing and diagnostic module(SDM). The SDM
performs a turn–on test when the ignition is turned ON.
The SDM flashes the airbag indicator seven times by sup-
plying an intermittent ground to the indicator lamp circuit.
After flashing seven times, the airbag indicator will turn off
if no more malfunctions have been detected.
If the SDM has detected malfunctions in the internal and
external circuits, which could potentially affect the opera-
tion of the supplemental inflatable restraints(SIR), the air-
bag indicator stays on. Some malfunctions could result in
non–deployment when necessary or deployment under
conditions which would not normally result in deployment.
When the SDM is not properly attached to its connector,
the airbag circuit is shorted to ground because there is a
shorting bar in the SDM electrical connector. The shorting
bar is disengaged when proper connection is made, but if
a poor connection exists the SDM connector supplied a
ground to the airbag indicator independently of the SDM,
and the airbag indicator turns on.
CLOCK SPRING
CAUTION : Disassembling the clock spring can cause
injury or cause the clock spring to malfunction.
CAUTION : Over–rotating the clock spring (over 3 and
one quarter turns to one direction) without the steer-
ing wheel in position could damage the clock spring
and result in an inoperative driver airbag.
There is a coil assembly in the steering which is referred
to as a clock spring because of its internal resemblance to
the type of spring used in a mechanical clock. The coil

8B – 102ISUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)
DAEWOO V–121 BL4
spring should never be disassembled, and there is no
timekeeping function. The clock spring contains two or
three current–carrying coils. One of the current–carrying
coils maintains continuous contact within the driver de-
ployment loop while the steering wheel is rotated. The
clock spring also contains coils that maintain continuous
contact for horn and remote audio control switch circuit.
Turning the steering wheel in one direction tightens the
coil, and turning the steering wheel in the opposite direc-
tion loosens the coil. Do not turn the clock spring when the
steering wheel is not attached. Refer to ”Clock Spring” in
this section for proper installation of the clock spring.
The clock spring also includes the wiring and the connec-
tors for the horn circuit and the driver airbag circuit. A yel-
low two–way connector on the lower steering column is at-
tached to the clock spring wiring. The yellow connector to
the airbag contains a shorting bar which connects the driv-
er high circuit to driver low circuit when the connector is
disconnected.
The shorting bar prevents current from travelling through
the driver airbag module during servicing. The shorting bar
is disengaged when the clock spring connector is con-
nected.WIRING HARNESS CONNECTORS
If the sensing and diagnostic module (SDM) electrical con-
nector is not attached properly, a built in shorting bar will
connect the wire from airbag warning lamp with the SDM
ground wire. This turns on the airbag indicator . To prevent
deployment during servicing, additional shorting bars are
located in following locations :
S The clock spring electrical connector at the lower
steering column.
S The passenger airbag module.
S The driver airbag module.
S The seat belt pretensioners.
The shorting bar is only a backup safety device. Always
disable the supplemental inflatable restraints(SIR) before
beginning any service procedure.

9B – 14ILIGHTING SYSTEMS
DAEWOO V–121 BL4
DIAGNOSIS
HEADLAMPS–ON REMINDER CHIME
Diagnostic Aids :
The fuse for the left–side taillamps is also part of the headlamps–on reminder chime circuit. The headlamps–on reminder
chime should operate when the ignition is OFF, the headlamps or parking lamps are on, and the driver door is open.
Headlamps–On Reminder Chime Does Not Work
StepActionValue(s)YesNo
1Turn the parking lamps on, and observe the tail-
lamps.
Are the taillamps operating correctly?–Go to Step 3Go to Step 2
2Repair the left–side taillamps before completing this
diagnostic table.
After the taillamps have been repaired, does the
headlamps–on reminder chime work?–System OKGo to Step 3
31. Disconnect the chime module electrical con-
nector.
2. Turn the headlamps on.
3. Check the voltage at terminal 6 of the chime
module connector.
Is the voltage equal to the specified value?11–14 vGo to Step 5Go to Step 4
4Repair the open circuit between fuse Ef23 and termi-
nal 6 of the chime module connector.
Is the repair complete?–System OK–
5Use an ohmmeter to check the resistance between
ground and terminal 5 of the chime module.
Is the resistance equal to the specified value?
0 WGo to Step 7Go to Step 6
6Repair the open circuit between ground and terminal
5 of the chime module.
Is the repair complete?–System OK–
71. Remove the driver door contact switch.
2. Remove the electrical connector from the driv-
er door contact switch.
3. Use an ohmmeter to measure the resistance
between the driver door contact switch connec-
tor and the chime module terminal 4.
Does the ohmmeter indicate the specified value?
0 WGo to Step 9Go to Step 8
8Repair the open circuit between the driver door con-
tact switch connector and the chime module termi-
nal 4.
Is the repair complete?–System OK–
91. Connect the electrical connector to the chime
module.
2. Connect a jumper wire between ground and
the connector for the driver door contact
switch.
3. Turn the ignition OFF.
4. Turn the lights on.
Does the headlamps–on reminder chime operate?–Go to Step 11Go to Step 10

9B – 16ILIGHTING SYSTEMS
DAEWOO V–121 BL4
HEADLAMPS
Low–Beam Headlamps Are Inoperative, High–Beam Headlamps
Are OK
StepActionValue(s)YesNo
1Check fuses Ef20 (left side headlamps) and Ef27
(right side headlamps).
Is fuse Ef20 or Ef27 blown?–Go to Step 2Go to Step 3
21. Check for a short circuit and repair if neces-
sary.
2. Replace the fuse.
Is the repair complete?–System OK–
3Check the voltage at fuses Ef20 and Ef27.
Does the voltage available at fuses Ef20 and Ef27
equal the value specified?11–14 vGo to Step 4Go to Step 9
41. Disconnect both headlamp connectors.
2. Turn the headlamps ON.
3. Select the low beams.
Does the voltage at each headlamp connector termi-
nal 5 equal the value specified?11–14 vGo to Step 6Go to Step 5
5Repair the open circuit between fuses Ef20 or Ef27
and the low beam headlamps.
Is the repair complete?–System OK–
61. Disconnect the headlamp connectors.
2. Connect an ohmmeter between ground and
either headlamp connector terminal 6.
Is the resistance equal to the value specified?0 WGo to Step 8Go to Step 7
7Repair the ground circuit.
Is the repair complete?–System OK–
8Replace the faulty headlamps.
Is the repair complete?–System OK–
91. Disconnect the headlamp switch connector.
2. Select the low beams.
3. Use an ohmmeter to check the continuity be-
tween terminals 6 and 5 of the headlamp
switch.
Does the ohmmeter indicate the value specified?0 WGo to Step 10Go to Step 11
10Replace the headlamp combination switch.
Is the repair complete?–System OK–
11Repair the open circuit between fuses Ef20 and Ef27
and the headlamp switch connector terminal 5.
Is the repair complete?–System OK–

9B – 18ILIGHTING SYSTEMS
DAEWOO V–121 BL4
High–Beam and Low–Beam Headlamps Are Inoperative On Both
Left and Right Sides
StepActionValue(s)YesNo
1Check fuses F6, Ef2, Ef20, Ef27 and Ef15.
Is any fuse blown?–Go to Step 2Go to Step 3
21. Check for a short circuit and repair if neces-
sary.
2. Replace the fuse.
Is the repair complete?–System OK–
31. Turn the low–beam headlamps ON.
2. Check the voltage at fuses Ef20, Ef27 and
Ef15.
Does the voltage at the headlamps equal the value
specified?11–14 vGo to Step 4Go to Step 9
41. Turn the low–beam headlamps ON.
2. Check the voltage at the headlamp connector
terminal 5.
3. Turn the high–beam headlamps ON.
4. Check the voltage at headlamp connector ter-
minal 4.
Does the battery voltage available at the headlamps
equal the value specified?11–14 vGo to Step 6Go to Step 5
5Repair the open circuit between fuses Ef20, Ef27
and Ef15 and the headlamps.
Is the repair complete?–System OK–
6Use an ohmmeter to check between ground and
each headlamp connector terminal 6.
Is the resistance equal to the specified value?0 WGo to Step 8Go to Step 7
7Repair the ground circuit.
Is the repair complete?–System OK–
81. Replace the faulty headlamps.
2. Check the charging system to make sure that
charging voltage is not excessively high. Re-
pair if necessary.
Is the repair complete?–System OK–
9Temporarily substitute the illumination relay in place
of the headlamp relay.
Do the headlamps operate with the substituted
relay?–Go to Step 10Go to Step 11
10Install the illumination relay in its original position,
and install a new headlamp relay.
Is the repair complete?–System OK–
111. With the headlamp relay removed, turn the
headlamp switch to the low–beam position.
2. Use an ohmmeter to check the continuity be-
tween the connector for relay terminal 85 and
ground.
Does the ohmmeter indicate the specified value?
0 WGo to Step 17Go to Step 12