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Anti-Theft System - Description/Key Registration: Overview

Classification:
EL02-015b

Reference:
NTB02-071b

Date:
April 16, 2004

ENGINE WILL NOT START NVIS/NATS SYSTEM DESCRIPTION/KEY REGISTRATION

This version of NTB02-071 amends the Applied Vehicles. Please discard all paper copies of the earlier version.

APPLIED VEHICLES:
2003 Murano (Z50)
2003 350Z (Z33)
2004 350Z (Z33) built before the following:

Date:
October 14, 2003

VIN:
JN1AZ34D(*)4T 160007
JN1AZ34D(*)4T 060009
JN1AZ36D(*)4T 110005
JN1AZ36A(*)4T 010006

NOTE:
For 2004 Murano, and 2004 350Z built after the above Date and VIN's see NTB03-031

SERVICE INFORMATION

^ This bulletin covers a new version of the Nissan Vehicle Immobilizer System/Nissan Anti-Theft System (NVIS/NATS). This system, referred to as "NATS", is standard equipment on the Applied Vehicles listed above.

^ NATS uses advanced anti-theft functions which are "password protected". This helps prevent "unauthorized access" into the NATS registration procedure.

^ Unlike earlier NATS systems, this NATS system DOES NOT need to be Re-Initialized if the Electronic Control Unit (ECM) is replaced.

NOTE:
The ECM and Body Control Module (BCM) do work together, but the BCM in this new system controls the information necessary to "tell" the ECM to start the vehicle.

IMPORTANT:
The NATS "Control Unit (C/U) Initialization and Key Registration" Procedure in this bulletin is for the Applied Vehicles only. Do not use this procedure on other NATS-equipped vehicles.





System Components (see Figure 1)

^ NATS ignition key (with transponder chip).

^ NATS antenna amplifier, located around the ignition key cylinder.

^ Body Control Module (BCM), located behind the driver's side left kick panel for 350Z and behind the driver's side lower knee panel for Murano.

^ Engine Control Module (ECM), located under the console, below the instrument panel.

^ Security indicator (Light Emitting Diode, or LED), located on the dash.

System Operation

^ The NATS uses a digital radio frequency (RF) to transmit a key code between the NATS key ID chip (which is "embedded" in the NATS ignition key) and the BCM.

^ When a registered NATS key transmits a "valid" (good) key code, the BCM will send a signal to the ECM that will allow the engine to start.

^ If the key doesn't "send" a good code, the BCM will not transmit a valid code to the ECM and the ECM will not let the engine start.

Special Service Notes:

Key Registration Required

^ NATS will not allow the engine to start without the use of a registered ignition key.





^ Previous and current Nissan models with NATS have a "Key I.D. chip" in the ignition key head (see Figure 2).

^ If a vehicle will not start and the Dash Security Lamp is ON solid, it is possible that the ignition keys were not properly registered into the vehicle's Body Control Module (BCM).

^ When a NATS ignition key is replaced, a new key added, or the BCM is replaced, the Control Unit (C/U) Initialization and Key Registration MUST BE PERFORMED or THE ENGINE WILL NOT START.

^ If a new ignition key(s) needs to be added or if any ignition key needs to be re-registered, ALL other ignition keys must be re-registered at the same time or they will no longer start the engine.

Other Important Information

^ When a NATS key is manufactured, the NATS key code is permanently encoded to the NATS key ID chip. This code cannot be changed.

^ It is recommend to use only Nissan service parts (key blanks).

^ NATS only allows the vehicle to start. It does not activate the vehicle theft warning system.

^ Each vehicle is supplied from the factory with three registered NATS ignition keys. A maximum of five ignition keys can be registered to the NATS.

Transponders

^ If a NATS-equipped vehicle experiences an intermittent "no-start" condition, another "transponder" could be causing "interference" (blocking the signal).

Examples of transponder interference:

> Other vehicle ignition keys that have transponders ("key I.D." chips). Either from the same vehicle or another model.





> Transponders such as the Mobil Speedpass(R) may be a source of interference (see Figure 3).

> These items may be too close (3/4 to 1 inch) to the registered key that is being used to start the vehicle.

^ In cases of interference from other keys or transponders, there will be a "DIFFERENCE OF KEY" code stored in the Engine Control Module (ECM). The MIL will not turn "ON" for this code.

^ Once the vehicle is started, transponder interference will not cause the engine to stall.

^ To avoid transponder interference, advise the customer to keep all other transponders on separate key rings.





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