2004 DAEWOO NUBIRA lock

9T2 – 4IIMMOBILIZER ANTI–THEFT SYSTEM
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1626 (MR–140,
HV–240), P1628 (SIRIUS)
ECM IMMOBILIZER ERROR (NO SUCCESSFUL
COMMUNICATION)
Circuit Description
When the ignition is turned ON, the key is tested by the im-
mobilizer anti–theft system. While the key code is being
read by the immobilizer control unit, the engine can start
and run with any key that will turn the lock cylinder. The key
code is read and compared with key codes that have been
stored in the memory of the immobilizer control unit. If a
valid key is detected, the immobilizer control unit sends a
serial data release message to the electronic control mod-
ule (ECM). Included in the release message is an identifi-
cation (ID) code which assures that neither the immobiliz-
er control unit nor the ECM has been substituted to defeatthe system. If the ECM receives an invalid release mes-
sage, the ECM performs the following actions:
S Disables the fuel injector circuit.
P1626, 1628 Will Set When
S The ECM does not receive the signal from the im-
mobilizer control module within 1.260 seconds after
the ignition is turned on.
S The above conditions are maintained until the igni-
tion is switched OFF.
P1626, 1628 Will Clear When
S The ignition switch is turned OFF or the scan tool
TROUBLE CODE CLEAR command is issued.

9T2 – 6IIMMOBILIZER ANTI–THEFT SYSTEM
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1631 (MR–140,
HV–240), P1629 (SIRIUS D4)
ECM IMMOBILIZER ERROR (INCORRECT ANSWER)
Circuit Description
When the ignition is turned ON, the key is tested by the im-
mobilizer anti–theft system. While the key code is being
read by the immobilizer control unit, the engine can start
and run with any key that will turn the lock cylinder. The key
code is read and compared with key codes that have been
stored in the memory of the immobilizer control unit. If a
valid key is detected, the immobilizer control unit sends a
serial data release message to the electronic control mod-
ule (ECM). Included in the release message is an identifi-
cation (ID) code which assures that neither the immobiliz-er control unit nor the ECM has been substituted to defeat
the system. If the ECM receives an invalid release mes-
sage, the ECM performs the following actions:
S Disables the fuel injector circuit.
P1631, 1629 Will Set When
S The ECM receives an incorrect release message
from the immobilizer control unit more than five
times.
P1631, 1629 Will Clear When
S The ignition switch is turned OFF or the scan tool
TROUBLE CODE CLEAR command is issued.

IMMOBILIZER ANTI–THEFT SYSTEM 9T2 – 11
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
IMMOBILIZER SYSTEM
The purpose of the Immobilizer system is to provide addi-
tional theft deterrence to the vehicle in which it is installed
and to prevent it from being stolen or driven by unautho-
rized users.
The verification of the user authorization is done by an igni-
tion key with integrated transponder.
The external LED displays the Immobilizer status and has
an additional theft deterrence function.
To secure the communication, the status is exchanged be-
tween the Immobilizer and the ECM in a 5 byte of encoded
data.
These 5 bytes are composed by a mixture of random data
and two types of fixed code
S a vehicle model identification number : MIN
S a vehicle specific identification : VIN
The MIN is known from the first supply of the system.
The VIN is realized by ICU on the special order from the
key coding (reading of transponder code and storing it as
valid key code in Immobilizer EEPROM).
A different random data is computed at each key transi-
tion.
All the immobilization communication between the ECM
and ICU is made on K–line (K line : Serial data line ’7’).
Due to the learning of the Vehicle specific identification
Number, both ICU and ECM can stay in 3 stable modes
S Virgin mode (VIN not learnt)
S Learnt mode (VIN learnt)
S Neutral mode (for a new VIN learning)
In case of using valid key, the release message commu-
nication with the ECM take place and the LED displays the
Immobilizer status valid key In case of using invalid key,
the ECM disables the fuel injector circuit with coded inter-
vention and sets DTC(Diagnostic Trouble Code)
The above conditions are maintained until the ignition is
switched off.
An ECM without an immobilizer control unit cannot be in-
terchanged for an ECM that is used with an immobilizer
control unit system. The Immobilizer control unit and ECM
must have a matching ID code. ID coding and key coding
are accomplished by using Scanner–100
The Immobilizer system consists of
S a maximum or 5 ignition keys with integrated trans-
ponder
S the toroidal coil (Detection coil) for energizing and
reading the transponder mounted at the ignition
lock.S the Immobilizer control unit(ICU) with :
– power supply
– ignition input circuit
– transponder modulation and demodulation unit
– EEPROM
– driver electronic for the external status LED
– serial data link hardware
S the external status LED for displaying the Immobi-
lizer status
S the serial data link between Immobilizer and ECM
ELECTRONICALLY CODED KEYS
Each valid ignition key has an internal transponder which
is a read /write transponder.
The transponder contains an implementation of a crypto–
algorithm with 96 bits of user configurable s cret–key con-
tained in EEPROM and transmits data to the ICU by mod-
ulating the amplitude of the ele tromagnetic field, and
receives data and commands in a similar way.
DETECTION COIL
The toroidal coil is mounted at the ignition lock in front of
the key barrel.
It is connected to the ICU with a four terminal connector
fixed at the body of the coil.
The length of the connection between coil and Immobilizer
is restricted to 50cm. The correct placement on the ignition
lock and the exact electrical data is very important for the
reading distance of transponder.
he toroidal coil and receiving coil inside the transponder
built a transformer. During the readingprocess the coil in-
duces energy into the transponder. The transponder
charges the field and generates an amplitude modulated
signal with the manchester coded data. This charge of the
field is demodulated inside the Immobilizer.
The Immobilizer contains the coil driver hardware for di-
rect connection of the toroidal coil.
IMMOBILIZER CONTROL UNIT
The function of the Immobilizer System is shared between
the ICU and the ECM.
The task of the Immobilizer Electronic Control unit (ICU)
are:
S Reading of the input information ”ignition ON/OFF”
S Controlling the states LED
S Controlling the transponder read/write process
(modulation, demodulation, decoding, comparison
of the read code with the code of the valid keys).
S Communication with the ECM after ignition ON (re-
ceiving of the ECM–request and transmission of
release message).
S Special functions for calculation and handling of the
VIN–code.
The VIN code is calculated by the Immobilizer using a ran-
dom generator.

9T2 – 12IIMMOBILIZER ANTI–THEFT SYSTEM
DAEWOO V–121 BL4
The VIN code is transmitted from the Immobilizer in the re-
lease message communication only incase of using an au-
thorized key. Without an authorized key it is not possible
to getthe system VIN code.In case of ECM internal state
is in Virgin mode or neutral mode the ECM learns the sys-
tem VIN code automatically after receiving the first release
response message.
To get a synchronized Immobilizer system (same VIN–
code in Immobilizer and ECM,authorized key) the DLC
test equipment has to be used for authorization of the
keys(first key coding). The usage of this test equipment is
restricted to authorized persons.
S Communication with the DLC–test equipment. Main
functions are the key coding procedure, the VIN–
code handling and the support for system test func-
tions.
S Handling of the software watchdog
Operation
In the active mode of immobilizer (engine OFF, IG key
OFF) the status LED isblinking as mode A. When ignition
is turned ON, the system wakes up and tries to read out
the transponder.
In case of the detection of a valid key , The release mes-
sage communication with the ECM takes place. The sta-
tus LED displays the Immobilizer state ”valid key”.
After turning off the ignition(ignition OFF detection similar
to the ECM ignition OFF detection), the Immobilizer
changes to the active mode. The status LED is blinking as
Mode A.
Data Link Connector (DLC) Mode
When the ignition is on, a scan tool can switch the immobi-
lizer control unit to the DLC mode for diagnostics, key cod-
ing and ID coding.
S The status LED is turned off during DLC–mode
S The Immobilizer will answer all correct messages,
which are defined as Immobilizer messages.
ID Code Handling
One of 65,535 VIN codes is stored in the immobilizer EE-
PROM.
The VIN code can be erased by using ”Reset VIN code”
command of the scan tool.
When the immobilizer control unit calculates a new VIN
code, ECM VIN code should be reset to get identical with
the immobilizer control unit’s.
During diagnostic procedures, the VIN code can be read
for comparison with the ECM VIN code by using the scan
tool’s ”Read immobilizer control unit VIN code” command.
SERIAL DATA LINK
Serial data can be exchanged between a scan tool and the
ECM and the Immobilizer control unit.
ELECTRONIC CONTROL MOUDLE
(ECM)
S ECM in Virgin mode
In this mode, the ECM knows only the model
vehicle identifier code.
The engine can be locked/unlocked.
ECM requests to ICU the VIN number. As soon
as the ECM receives two correct consecutive
communication frames with the same VIN code
the ECM learns it.
The VIN code will be stored in non–volatile
memory at the end of power latch phase. ECM
enters in Learnt mode.
S ECM in Learnt mode
In such a state, ECM checks on every commu-
nication, the correct encoding of the ICU.
If the code received is not correct, then the vehicle is im-
mobilized.
The coded 5 bytes of data emitted by ECM are
a mixture of MIN code and random.
The coded 5 bytes of data emitted by ICU are a
mixture of VIN code and random.
S ECM in Neutral mode
This mode is a special intermediate mode, used
for ICU replacement or immobilizer option instal-
lation.
ECM request to ICU the VIN number. As soon
as the ECM receives two correct consecutive
communication frames with the same VIN code
the ECM learns it. The VIN code will be stored
in non–volatile memory at the end of power latch
phase. ECM enters in Learnt mode.
S After turning on the ignition the ECM will control the
engine in a normal way for starting and running
while waiting for a valid release response message
from the Immobilizer.

IMMOBILIZER ANTI–THEFT SYSTEM 9T2 – 13
DAEWOO V–121 BL4
1. After receiving a response message including the
information ”ICU in learnt mode” and the correct
system VIN–code

the ECM enters the release state, which al-
lows to continue the running of the engine.
2. After receiving a response message including the
information ”ICU in learnt mode” and a wrong sys-
tem VIN–code

the ECM does not send a new request and
enters the blocked state, which causes the ac-
tivation of the immobilization actions of the en-gine.
3. If the ECM doesn’t receive a response message
within a defined time from beginning of the release
time period or the ECM receives a no release an-
swer

the ECM enters the blocked state, which
causes the activation of the immobilization ac-
tions of the engine.
S The inactive state of the Immobilizer (valid key/
invalid key) ends with turning off the ignition.

2–4 PREPARATIONS OF BODYWORK NUBIRA/LACETTI
2. CHECKPOINTS
S Accurate Inspection of Damaged Parts(Visual)
.
Seat Belts
Always replace the seat belt if :
1. The belt material is cut, punctured, burned or in any
way damaged.
2. The buckle or retractor does not work properly.
3. They were being worn at the time of a collision(also
check for damage at the seat belt anchor points).
4. Their condition is questionable.
.
Front Section :
1. Is there any bending, splitting, denting or other dam-
age to the suspension and its related parts?
2. Is there any deformation of the front panel or radiator
crossmember? Have any of the connected sections
come apart?
3. Are there any creases or distortion in the front wheel-
house or side frame? Have any of the connected sec-
tions come apart?
4. Is there any bending or twisting of the whole front
area?
5. Is there any deformation like creases, bulges, or dents
in the front pillar, dash panel, floor, etc.?
6. Is there any vertical twisting or misaligned clearance
in the door?
7. Is the windshield seal broken?
8. Is there any deformation in the vicinity of the top part
of the roof panel’s center pillar?
9. Is there any damage inside the automobile(is there
any twisting of the dash panel, or anything irregular with
the clearances or sheet–mounting parts)?
10. Is there any damage to the steering wheel? Is there
any deformation in the column and the column–mounted
parts?
11. Is there any oil or water leakage and damage to the en-
gine, transmission or brakes?
12. Is there any irregular noise in the gear changing opera-
tion, engine and transmission rotation?
13. Are there any traces of contact between the engine
block and the center crossmember ?
14. Is there any damage to brake or fuel lines, or wire har-
nesses?Rear Section :
1. Is there any twisting, bulging or denting of the rear floor
any rear bolsters? Have any of the connected sections
come apart?
2. Is there any irregular bulging or denting in the rear
fender?
3. Is there any distortion in the rear inner panel? Is there
any bending and denting in the vicinity of the rear pillar?
4. Is there any distortion or creasing is the rear wheel-
house and arch sections? Have any of the connected
sections come apart?
5. Is there anything irregular in the rear glass seal clear-
ance?
6. Is there any twisting or misalignment of the clearance
of the trunk lid opening section?
7. Is there any bending, splitting, denting or other dam-
age to the suspension and its related parts?
8. Is there any deformation of the rear floor crossmem-
ber, trunk floor panel and back panel? Have any of the
connected sections come apart?
.
Impact Beam :
Always replace the door assembly if :
1. The external force makes the impact beam of door in-
ner deform.
Always replace impact beam if :
2. The external force makes the impact beam of front
bumper and rear bumper deform.

NUBIRA/LACETTIFRONT 4–5
S Aircon condenser and related parts.
S Head lamps and fenders.
S Hood, radiator grill, and bumper.
S Others
S Install in the reverse order in which they were removed.
Note : After install the all related parts, rub in grease to
the moving parts and replenish cooling liquid, break oil,
aircon gas and others.
14. Check and adjust
S Check clearances and level differences.
S Check the hood locking and unlocking condition.
S Adjust the head lamp aim.
S Check all operation.
S Check for gas, oil and liquid leaks.
Note : Use specified check sheet for operation check
properly.

NUBIRA/LACETTIFRONT 4–9
Fig. 14
11. Weld the brace wheelhouse.
S Spot weld the brace wheelhouse as shown.
S Make MIG or gas welds at the door hinge areas.
Fig. 15
12. Finish the welding areas.
S Use a hammer and dolly to even out the rear wheel-
house and front longitudinal flanges for a close fit with
the surface of the front wheelhouse.
13. Apply the sealer
S Apply the sealer to the matching and overlapped sur-
face.
14. Apply the undercoat.
S Undercoat to the inside of the front, rear wheelhouse
and longitudinal.
15. Apply the paint.
CAUTION
S Ventilate when spraying paint. Most paint contains sub-
stances that are harmful if inhaled or swallowed. Read
the paint label before opening paint container.
S Avoid contact with skin. Wear an approved respirator,
gloves, eye protection and appropriate clothing when
panting.S Paint is flammable. Store in a safe place, and keep it
away from sparks, flames or cigarettes.
16. Coating the anti–rust agents.
S Coating the anti–rust agents to the end of front panel
side and the door hinge areas.
17. Install the related parts.
S Wiring harness, instrument panel and related parts.
S Parts of the passenger compartment.
S Parts to be installed when install the front panel.
S Others.
S Install in the reverse order in which they were removed..
Note : After install the all related parts, rub in grease to
the moving parts and replenish cooling liquid, break oil,
aircon gas and others.
18. Check and adjust
S Measure the front wheel alignment.
S Check clearances and level differences.
S Check the hood locking and unlocking condition.
S Adjust the head lamp aim.
S Check all operation.
S Check for gas, oil and liquid leaks.
Note : Use specified check sheet for operation check
properly.