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SECTION 9T2

IMMOBILIZER ANTI-THEFT SYSTEM

Caution : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.

SPECIFICATIONS

Fastener Tightening Specifications

Application
N•m
Lb-Ft
Lb-In
Steering column nut
22
16
-
Steering column bolt
22
16
-

SCHEMATIC AND ROUTING DIAGRAMS

Immobilizer Anti-Theft System


V5B19T02
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MAINTENANCE AND REPAIR

On-Vehicle Service

Key Coding Procedure

    Caution : When learn the transponder key, does not take keys, at the same time.

    Caution : After ignition on, K-line is cut off max 3 seconds.

    Caution : If the transponder learnt, RKE is also learnt, automatically.

    Caution : The master key's access code must not forget and leaked.

  1. Connect the Scan 100 Scan Tool to the Data Link Connector(DLC).
  2. Turn the Scan 100 Scan Tool ”ON” by pressing the "Power" Button, then wait for the MAIN MENU screen to be displayed.
  3. From the MAIN MENU screen, select "Diagnostics" by pressing #1 on the Key Pad.
  4. From the MODEL YEAR screen, select the appropriate model year of the specific vehicle by either scrolling down to the year and pressing "ENTER", or by pressing the respective item number on the Key Pad.
  5. From the VEHICLE TYPE screen, select the specific vehicle model by either scrolling down to the model name and pressing "ENTER", or by pressing the respective item number on the Key Pad.
  6. From the SYSTEM SELECTION MENU screen, select "Body" by pressing #2 on the Key Pad.
  7. From the BODY SELECTION MENU screen, select "Coding" by pressing #3 on the Key Pad.
  8. From the CODING SYSTEM screen, select "Coding Only" by pressing #1 on the Key Pad.
  9. From the SECRET NUMBER OF CODINGS screen, enter for(4) zero's (0–0–0–0) in the for(4) boxes labeled "1–2–3–4".
  10. From the CODING SYSTEM SELECT screen. Select "IMMOBILIZER" by pressing #1 on the keypad.
  11. Notice : A slight delay may occur and "PLEASE WAIT" may be displayed before the next screen appears.

  12. From the FUNCTION SELECTION screen, Select "KEY CODING" by pressing #1 on the keypad.
  13. From the IMMOBILIZER KEY CODING screen, enter six(6) Access Code in the six(6) boxes labeled "00-00-00".
  14. Continue programming immobilizer key coding when directed by the Scan 100 Scan Tool until all immobilizer key coding have been programmed.
  15. Notice : The ECU of the immobilizer can keep a maximum of 4 key codes.

    Notice : If the transponder learnt, RKE is also learnt, automatically.

  16. Once all transponder have been programmed, press the "ESC" button on the keypad. The display will confirm the number of transponder.
  17. Turn the Scan 100 Scan Tool "OFF" by pressing the "POWER" button, then disconnect it from the Data Link Connector.

ISU Replacement

If an ISU control unit in virgin mode doesn't detect any ignition ON transition with a virgin master key, It waits for a Diagnosis request key learning start which allows to get the Access code corresponding to the vehicle and registered at the Factory.

Case A

    If the first key detected at the Ignition On transition is locked and well programmed (authentication by encryption), the ISU memorizes the serial number of this key (used as identifier), and validates this key (increasing the number of learnt keys). Then and, up to 3 more keys can be learnt by successive lgnition On transitions whatever the key status (locked or virgin).
    The Learning mode ends :
    - By validation with a Diagnosis request key learning end. The keys are definitively saved, the flag keys learning successful is set, and the ISU switches to nominal mode operation (learnt mode) ; It is now ready to emit the VIN-code to EMS control unit at the next lgnition ON transition.
    - By cancellation with Diagnosis request cancel key learning, or time-out expiring, or power supply cut-off. The ISU returns then in its previous configuration (virgin mode).

Case B

If the first key detected at the Ignition On transition is locked but not well programmed (authentication by encryption), the key is refused, but the Learning mode stays on.
It is possible to present other key (case of a key mistake), or to restart the Learning procedure by entering another Access code ( case of code mistake).
The Learning mode ends in the same way than previous case.

Case C

    If the first key detected at the lgnition On transition is virgin (non locked), we have to consider the CALAVCOL parameter value :
    This parameter allows the simultaneous replacing of the ISU and the set of keys.
    - If CALAVCOL = 1, the ISU learns this key (by programming, authenticating and eventually locking it), but goes out of Learning mode, does not accept any additional key, and switches to nominal mode operation (learnt mode). The KTR secret key is not yet validated, and it can be changed by a new Diagnosis request key learning start, entering another Access code ( of Virgin Master Key).
    This allows to verify that the Immobilizer system is well synchronized (with the EMS control unit) by a cranking test. The KTR is validated automatically after 10 Ignition On transitions, or with a validation by Diagnosis request. The KTR validation status is saved to can resist to a power supply cut-off. Other keys can be learnt by executing the New keys affectation procedure
    - If CALAVCOL = 0, the key is refused, and the Learning procedure is cancelled as soon as the Ignition is switched OFF (return to the ISU previous configuration : virgin mode).
    It is then necessary to start again the procedure.

Key Replacement

    This is the procedure used in After Market to replace the keys, or to learn additional keys.
    If an ISU control unit in learnt mode receives the Diagnosis request key learning start which allows to get the Access code corresponding to the vehicle and registered at the Factory,
    - If the key detected at the Ignition On transition is locked, the ISU tries to authenticate it.
    If it is well programmed (authentication by encryption), the ISU memorizes the serial number of this key (used as identifier), and validates this key (increasing the number of learnt keys).
    If not, the key is refused : the learning of this key is not successful.
    The ISU waits for a new Ignition ON transition.
    - If the key detected at the Ignition On transition is virgin (non locked), the ISU learns this key (by programming, authenticating and eventually locking it).
    The Learning mode ends :
    - By validation with a Diagnosis request key learning end. The keys are definitively saved, and the flag keys learning successful is set, and the ISU switches to nominal mod operation (learnt mode) ; It is now ready to emit the VIN-code to EMS control unit at the next Ignition ON transition.
    - By cancellation with Diagnosis request cancel key learning, or time-out expiring, or power supply cut-off.

External Feedback

    Some information contained in Diagnosis data frames are updated during the keys learning and allow the operator to follow the procedure and to diagnostic in case the procedure fails :
    - Key's transponder is locked.
    - Key type is Master.
    - Key type is RF.
    - ISU learning status (learnt mode / virgin mode).
    - Number of learnt keys.
    - First key learning successful (Factory only).
    - Keys learning successful .
    - Status of each RF key (learnt / synchronized).


V3B39E11
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Head Amp (Immo Demodulator)

Removal Procedure

  1. Disconnect the negative battery cable.
  2. Remove the knee bolster. Refer to Section 9G, Interior Trim.
  3. Remove the instrument cluster trim panel. Refer to Section 9E, Instrumentation/Driver Information.


  4. V3B39B17
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  5. Remove the steering column upper and lower cover.
  6. Remove the nuts and the bolts securing the steering column.
  7. Disconnect the steering column electrical connector.
  8. Lower the steering column.


  9. V3B39B29
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  10. Remove the screw and the head amp (IMMO demoduator).


V3B39B29
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Installation Procedure

  1. Install the head amp (IMMO demodulator) with the screw.


  2. V3B39B17
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  3. Raise the steering column.
  4. Connect the steering column electrical connector.
  5. Install the nuts and the bolts securing the steering column.
  6. Tighten
    Tighten the steering column nuts to 22 N•m (16 lb-ft).
    Tighten the steering column bolts to 22 N•m (16 lb-ft).

  7. Install the steering column upper and lower cover.


  8. V3B39E11
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  9. Install the instrument cluster trim panel. Refer to Section 9E, Instrumentation/Driver Information.
  10. Install the knee bolster. Refer to Section 9G, Interior Trim.
  11. Connect the negative battery cable.

GENERAL DESCRIPTION AND SYSTEM OPERATION

Immobilizer System

The purpose of the IMMO system is to provide and additional anti-theft to the vehicle which is installed in, preventing it from an unauthorized use. Checking of user authorization is done by use of an ignition key whose head integrates a crypto-transponder. The Described system is a transponder-based immobilizer for an automotive vehicle.
The products constituting the application are the following ones :
- Up to 4 ignition keys with transponder integrated in the key head.
- The antenna (toroidal coil) for energizing and communicate with the transponder with its integrated electronic modulator/demodulator driver.
- The ISU control unit (Intelligent Switching Unit), in which Immobilizer function is managed.
- The ECM control unit (Engine Control Management).
- The external status indicator (LED) for displaying the Immoblilzer status.
- The serial data link between ISU and EMS control unit.
- The data link and supply link between ISU control unit and antenna Plus the standard components, conforming to Diagnostic standard Keyword Protocol 2000 :
- The Diagnostic Tester.
- The serial data link (K line) between Tester and vehicle ECM (Electronic Control Module).
Only Immobilizer related requirements of the ISU control unit and ECM control unit are described in this document.

Key with Integrated Transponder

The key is constituted with :
- A mechanical part (metallic key).
- A transponder component.
- Top and bottom shells.
For the Radio Frequency Remote Control key (FR/TR key), the key contains also an electronic transmitter PCB, a buttons set and a battery.
The used transponder is the TIRIS DST crypto transponder.

Antenna(Toroidal Coil)

The antenna is a toroidal coil allowing to create the electromagnetic field necessary for transponder operation.
The antenna is mounted at the ignition lock. It is connected to the antenna driver (electronic PCB integrated in the body of the coil).
This driver is connected to the ISU control unit with a four terminal connector.
The antenna is used for transponder operation, based on a sequential function principle :
- Transponder powering (charge) phase, during which the antenna generates an electromagnetic field using a frequency of 134.2 kHz ; this field induce energy into the transponder by way of this resonant circuit.
- Write phase : sued to transfer commands, addresses and data to the transponder ; the principle is a pulse width modulation of the previous electromagnetic field.
- Read phase : the antenna is used as receiver, which demodulates the transponder response signal which is modulated using Frequency Shift Keying.

ISU(Intelligent Switching Unit)

Tasks

The ISU is the Car-body control unit, which realizes some functions as actuators control, vehicle access control or alarm function.
The Immobilizer function is shared between the ISU and the ECM control units.
The Immobilizer tasks of the ISU are :
- Communication with the key's transponder after Ignition ON transition (identification and authentication of the key, learning of the keys).
- Communication with the ECM control unit after Ignition ON transition (receipt of the ECM request and transmission of release message).
- Control of the Immobilizer status indicator (LED).
- Communication with the Diagnosis tester (keys learning, diagnostic).

Immobilizer Function

The Immobilizer function of ISU control unit has three main modes :
- The Immobilizer active mode, selected when Ignition key is OFF. In this mode, the status indicator (LED) is driven in mode A or B (see Status indicator chapter), depending of the Alarm function status (armed of disarmed), (cranking is not possible).
- The Nominal mode, selected when Ignition key is switched ON and Nominal mode condition is verified. It is the current mode of use. In this mode, 2 function states are considered :
- The Learning mode, selected when Ignition key is switched ON and Learning mode condition is verified.

Serial Data Link

Serial data can be exchanged between a scan tool, electronic control module (ECM), and the intelligent switching unit (ISU). The scan tool connection is the data link connector (DLC).

Electronic Control Module (ECM)

When the electronic control module (ECM) detects that the ignition is being turned ON, the ECM waits for a release message from the intelligent switching unit. If a release message is not received within a specified time, the ECM disables the engine. The engine is also disabled if the identification (ID) code transmitted by the intelligent switching unit does not match the code stored in the ECM's memory. Immobilization remains in effect until the ignition is turned OFF or battery power is removed.
To prevent the vehicle from being driven, the ECM applies the following strategy:
Serial data communication is transmitted on a single wire between the intelligent switching unit and the ECM.
During diagnostic procedures or ID code changing, a scan tool is added to the communication system.
An ECM with an intelligent switching unit is not exchangeable with the ECM without an immobilizer control unit.


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