2004 DAEWOO LACETTI transmission

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.

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.

4–10 FRONTNUBIRA/LACETTI
3. FRONT LONGITUDINAL
3–1. GENERAL DESCRIPTION
The front longitudinal is joined to the wheelhouse and
front panel, it forms the base for the front suspension,
engine, transmission and others. Therefore, replace-ment of the component affects the front wheel align-
ment and maintains the rigidity of the front section.
When assembling it, either use a jig or follow dimen-
sions on the body repair chart for positioning. It must be
welded carefully.
Fig. 16 Front Longitudinal Welding Assembly