Security Control System: Overview Nissan Quest IV

SYSTEM DESCRIPTION

1. The engine start function of Intelligent Key system makes it possible to start and stop the engine without using the key, based on the electronic ID verification. The electronic ID verification is performed between BCM and Intelligent Key when the push-button ignition switch is pressed while the Intelligent Key is within the detection area of inside key antenna. NOTE: The driver should carry the Intelligent Key at all times.
2. Intelligent Key has 2 IDs [Intelligent Key ID and NVIS (NATS) ID]. It can perform the door lock/unlock operation and the push-button ignition switch operation when the registered Intelligent Key is carried.
3. If the ID is successfully verified, when push-button ignition switch is pressed, the engine can be started.
4. Up to 4 Intelligent Keys can be registered (Including the standard Intelligent Key) upon request from the customer. NOTE: Refer to " «INTELLIGENT KEY SYSTEM: SYSTEM DESCRIPTION»(/nissan/quest/iv-2010-2024/remont/door-locks-anti-theft-systems/#door-lock) " for any functions other than engine start function of Intelligent Key system.

OPERATION WHEN INTELLIGENT KEY IS CARRIED

1. When the push-button ignition switch is pressed, the BCM activates the inside key antenna and transmits the request signal to the Intelligent Key.
2. The Intelligent Key receives the request signal and transmits the Intelligent Key ID signal to the BCM.
3. BCM receives the Intelligent Key ID signal via remote keyless entry receiver and verifies it with the registered ID.
4. BCM turns ACC relay ON and transmits the ignition power supply ON signal to IPDM E/R.
5. IPDM E/R turns the ignition relay ON and starts the ignition power supply.
6. IPDM E/R turns the starter control relay ON for engine starting in advance.
7. BCM detects the selector lever position and brake pedal operation condition.
8. BCM transmits the 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.
9. Power supply is supplied through the starter relay and the starter control relay to operate the starter motor. CAUTION: If a malfunction is detected in the Intelligent Key system, the "KEY" warning lamp on the combination meter illuminates. At that time, the engine cannot be started.
10. When BCM receives feedback signal from ECM indicating that the engine is started, the BCM transmits a stop signal to IPDM E/R and stops cranking by turning OFF the starter relay. (If engine start is unsuccessful, cranking stops automatically within 5 seconds.) CAUTION: When the Intelligent Key is carried outside of the vehicle (inside key antenna detection area) while the power supply is in the ACC or ON position, even if the engine start condition * is satisfied, the engine cannot be started.

*: For the engine start condition, refer to " IGNITION SWITCH POSITION CHANGE TABLE BY PUSH-BUTTON IGNITION SWITCH OPERATION ".

OPERATION RANGE

Engine can be started when Intelligent Key is inside the vehicle. However, sometimes engine may not start when Intelligent Key is on instrument panel or in glove box.

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

When Intelligent Key battery is discharged, NVIS (NATS) ID verification between transponder in Intelligent Key and BCM is performed when Intelligent Key backside is contacted to push-button ignition switch while brake pedal is depressed. If the verification result is OK, engine can be started.

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

The ignition switch position can be changed by the following operations.

Note. When an Intelligent Key is within the detection area of inside key antenna or 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, CVT models Brake pedal operation condition Selector lever position Vehicle speed

VEHICLE SPEED SPECIFICATION - LESS THAN 4 KM/H (2.5 MPH)

VEHICLE SPEED SPECIFICATION - 4 KM/H (2.5 MPH) OR MORE

Emergency stop operation

1. Press and hold the push-button ignition switch for 2 seconds or more.
2. Press the push-button ignition switch 3 times or more within 1.5 seconds.

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1. The Nissan Vehicle Immobilizer System-NATS [NVIS (NATS)] prevents the engine from being started by Intelligent Key whose ID is not registered to the vehicle (BCM). It has higher protection against auto theft involving the duplication of mechanical keys.
2. The ignition key integrated in the Intelligent Key cannot start the engine. When the Intelligent Key battery is discharged, the NVIS (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 while brake pedal is depressed. If the verification result is OK, the engine start operation can be performed by the push-button ignition switch operation.
3. Locate the security indicator lamp and always blinks it when the ignition switch is in any position except ON to warn that the vehicle is equipped with Nissan Anti-Theft System (NATS).
4. Up to 4 Intelligent Keys can be registered (including the standard ignition key) upon request from the owner.
5. When replacing ECM, BCM or Intelligent Key, the specified procedure (Initialization and registration) using CONSULT is required.
6. Possible symptom of NATS malfunction is "Engine can not start". This symptom also occurs because of other than NATS malfunction, so start the trouble diagnosis according to " «WORK FLOW»(ref-672643-S08199694052014112400000) ".
7. If ECM other than genuine part is installed, the engine cannot be started. For ECM replacement procedure, refer to " «ECM: WORK PROCEDURE»(ref-672643-S14948856922014112400000) ".

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 NVIS (NATS) ID verification between BCM and Intelligent Key (transponder built-in) via NATS antenna amp.
3. When NATS ID verification result is OK, buzzer in combination meter sounds and BCM transmits the result to ECM.
4. 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 and starts the ignition power supply.
6. IPDM E/R turns the starter control relay ON for engine starting in advance.
7. BCM detects that the selector lever position and brake pedal operation condition.
8. 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.
9. Power supply is supplied through the starter relay and the starter control relay to operate the starter motor.
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 " «IGNITION SWITCH POSITION CHANGE TABLE BY PUSH-BUTTON IGNITION SWITCH OPERATION»(ref-672643-S05583422602014112400000) " below.

The ignition switch position can be changed by the following operations.

Note. When an Intelligent Key is within the detection area of inside key antenna or 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, CVT models Brake pedal operation condition Selector lever position Vehicle speed

VEHICLE SPEED SPECIFICATION - LESS THAN 4 KM/H (2.5 MPH)

VEHICLE SPEED SPECIFICATION - 4 KM/H (2.5 MPH) OR MORE

Emergency stop operation

1. Press and hold the push-button ignition switch for 2 seconds or more.
2. Press the push-button ignition switch 3 times or more within 1.5 seconds.

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1. The vehicle security system has two alarm functions (theft warning alarm and panic alarm), and reduces the possibility of a theft or mischief by activating horns and headlamps intermittently.
2. The panic alarm does not start when the theft warning alarm is activating, and the panic alarm stops when the theft warning alarm is activated.

The priority of the functions are as per the following.

ECM: Description

Performing the following procedure can automatically activate recommunication of ECM and BCM, but only when the ECM is replaced with a new one*.

*: New one means a virgin ECM that has never been energized on-board. (In this step, initialization procedure using CONSULT is not necessary)

Note. When registering new Key IDs or replacing the ECM that is not brand new, the initialization of BCM using CONSULT is necessary. If multiple keys are attached to the key holder, separate them before beginning work. Distinguish keys with unregistered key IDs from those with registered IDs.

Description

ECM forcibly switches to the mode that inhibits engine start, when engine start operation is performed 5 times or more while communication between ECM and BCM is not normal.

BCM performs ID verification between BCM and dongle unit.

When verification result is OK, BCM permits cranking.

BCM receives the engine status signal from ECM via CAN communication.

Engine does not start when push-button ignition switch is pressed while carrying Intelligent Key.

Note. Check that vehicle is under the condition shown in "Conditions of vehicle" before starting diagnosis, and check each symptom. The engine start function, door lock function, power distribution system, and NATS-IVIS/NVIS in the Intelligent Key system are closely related to each other regarding control. The vehicle security function can operate only when the door lock and power distribution systems are operating normally.

Security indicator lamp does not blink when ignition switch is in a position other than ON.

Note. Before performing the diagnosis, check "Work Flow". Refer to " WORK FLOW ". Check that vehicle is under the condition shown in "CONDITIONS OF VEHICLE (OPERATING CONDITIONS)" before starting diagnosis, and check each symptom.

INTELLIGENT KEY: Description

Armed phase is not activated when all doors are locked using Intelligent Key.

Note. Check that vehicle is under the condition shown in "CONDITIONS OF VEHICLE (OPERATING CONDITIONS)" before starting diagnosis, and check each symptom.

DOOR REQUEST SWITCH: Description

Armed phase is not activated when all doors are locked using door request switch.

Note. Check that vehicle is under the condition shown in "CONDITIONS OF VEHICLE (OPERATING CONDITIONS)" before starting diagnosis, and check each symptom.

DOOR KEY CYLINDER: Description

ARMED phase is not activated when all doors are locked using mechanical key.

Note. Check that vehicle is under the condition shown in "Conditions of vehicle" before starting diagnosis, and check each symptom.

DOOR LOCK AND UNLOCK SWITCH: Description

Armed phase is not activated when all doors are locked by door lock and unlock switch.

Note. Check that vehicle is under the condition shown in "CONDITIONS OF VEHICLE (OPERATING CONDITIONS)" before starting diagnosis, and check each symptom.

Alarm does not operate when alarm operating condition is satisfied.

Note. Check that vehicle is under the condition shown in "CONDITIONS OF VEHICLE (OPERATING CONDITIONS)" before starting diagnosis, and check each symptom.

See also:
• DOOR LOCK SYSTEM: COMPONENT PARTS LOCATION
• REMOVAL AND INSTALLATION