System Description

SYSTEM

INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS : System Description


SYSTEM DESCRIPTION

- The IVIS (NATS) is an anti-theft system that registers an Intelligent Key ID to the vehicle (BCM) and prevents the engine from being started by an unregistered Intelligent Key. It has higher protection against auto theft involving the duplication of mechanical keys.
- The ignition key integrated in the Intelligent Key cannot start the engine. When the Intelligent Key battery is discharged, the IVIS (NATS) ID verification is performed between the transponder integrated with Intelligent
Key and BCM via NATS antenna amp. when the Intelligent Key backside is contacted to push-button ignition switch. If the verification result is OK, the engine start operation can be performed by the push-button ignition switch operation.
- Security indicator lamp is located on combination meter, and always blinks when the power supply position is any position other than ON to warn that the vehicle is equipped with IVIS (NATS).
- Up to 4 Intelligent Keys can be registered (including the standard ignition key) upon request from the owner.
- When replacing ECM, BCM, steering lock unit (Models with steering lock unit) or Intelligent Key, the specified procedure (Initialization and registration) using CONSULT is necessary.
- Possible symptom of IVIS (NATS) malfunction is "Engine does not start". However, this symptom also occurs because of other than IVIS (NATS) malfunction, so start the trouble diagnosis according to {LINK_TO:0000000006888029}, "Work
Flow".
- If ECM other than genuine part is installed, the engine cannot be started. For ECM replacement procedure, Work Procedure (VQ-37VHR) or Work Procedure (VK-56VD).

PRECAUTIONS FOR KEY REGISTRATION

- The ID registration is a procedure that erases the current IVIS (NATS) ID once, and then reregisters a new
ID. Therefore before starting the registration operation, collect all registered Intelligent Keys from the customer.
- When registering the Intelligent Key, perform only one procedure to simultaneously register both ID [IVIS
(NATS) ID and Intelligent Key ID].

SECURITY INDICATOR LAMP

- Security indicator lamp warns that the vehicle is equipped with IVIS (NATS).
- Security indicator lamp always blinks when the power supply position is any position other than ON.
NOTE:
Because security indicator lamp is highly efficient, the battery is barely affected.

ENGINE START OPERATION WHEN INTELLIGENT KEY IS CONTACTED TO PUSH-BUTTON IGNITION SWITCH


Models with steering lock unit
1.When brake pedal is depressed while selector lever is in the P position, BCM activates NATS antenna amp. that is located behind push-button ignition switch.
2.When Intelligent Key (transponder built-in) backside is contacted to push-button ignition switch, BCM
starts IVIS (NATS) ID verification between BCM and Intelligent Key (transponder built-in) via NATS
antenna amp.
3.When IVIS (NATS) ID verification result is OK, buzzer in combination meter sounds and BCM transmits the result to ECM.
4.When push-button ignition switch is pressed, BCM transmits steering unlock signal to steering lock unit and IPDM E/R.
5.IPDM E/R turns steering lock relay ON to supply power source to the steering lock unit.
6.The steering lock is released.
7.BCM transmits the power supply stop signal to IPDM E/R when detecting that the steering lock is in the unlock position.
8.IPDM E/R turns steering lock relay OFF to stop power supply to the steering lock unit.
9.BCM turns ACC relay ON and transmits ignition power supply ON signal to IPDM E/R.
10.IPDM E/R turns the ignition relay ON to start the ignition power supply.
11.BCM detects that the selector lever position is P or N.
12.BCM transmits starter request signal to IPDM E/R and turns the starter relay in IPDM E/R ON if BCM
judges that the engine start condition* is satisfied.
13.IPDM E/R turns the starter control relay ON when receiving the starter request signal.
14.Power source is supplied to the starter motor through the starter relay and the starter control relay.
15.When BCM receives feedback signal from ECM indicating that the engine is started, BCM transmits a stop signal to IPDM E/R and stops cranking by turning off the starter motor relay. (If engine start is unsuccessful, cranking stops automatically within 5 seconds.)
*: For the engine start condition, refer to "POWER SUPPLY POSITION CHANGE TABLE BY PUSH-BUTTON
IGNITION SWITCH OPERATION" below.
Models without steering lock unit
1.When brake pedal is depressed while selector lever is in the P position, BCM activates NATS antenna amp. that is located behind push-button ignition switch.
2.When Intelligent Key (transponder built-in) backside is contacted to push-button ignition switch, BCM
starts IVIS (NATS) ID verification between BCM and Intelligent Key (transponder built-in) via NATS
antenna amp.
3.When IVIS (NATS) ID verification result is OK, buzzer in combination meter sounds and BCM transmits the result to ECM.
4.When push-button ignition switch is pressed, BCM turns ACC relay ON and transmits ignition power supply ON signal to IPDM E/R.
5.IPDM E/R turns the ignition relay ON to start the ignition power supply.
6.BCM detects that the selector lever position is P or N.
7.BCM transmits starter request signal to IPDM E/R and turns the starter relay in IPDM E/R ON if BCM
judges that the engine start condition* is satisfied.
8.IPDM E/R turns the starter control relay ON when receiving the starter request signal.
9.Power source is supplied to the starter motor through the starter relay and the starter control relay.
10.When BCM receives feedback signal from ECM indicating that the engine is started, BCM transmits a stop signal to IPDM E/R and stops cranking by turning off the starter motor relay. (If engine start is unsuccessful, cranking stops automatically within 5 seconds.)
*: For the engine start condition, refer to "POWER SUPPLY POSITION CHANGE TABLE BY PUSH-BUTTON
IGNITION SWITCH OPERATION" below.

POWER SUPPLY POSITION CHANGE TABLE BY PUSH-BUTTON IGNITION SWITCH OPERATION

The power supply position changing operation can be performed with the following operations.
NOTE:
- When an Intelligent Key is within the detection area of inside key antenna and when Intelligent Key backside is contacted to push-button ignition switch, it is equivalent to the operations below.
- When starting the engine, the BCM monitors under the engine start conditions, - Brake pedal operating condition
- Selector lever position
- Vehicle speed
Vehicle speed: less than 4 km/h (2.5 MPH)





Vehicle speed: 4 km/h (2.5 MPH) or more