Intelligent Key System/engine Start Function

System Description

System Description

SYSTEM DIAGRAM

SIGNAL TRANSMISSION FUNCTION LIST

Signal name	Input	Output	Description
Inside key antenna signal	Intelligent Key unit	BCM (CAN) IPDM E/R (CAN)	Inputs the inside key antenna signal via CAN communication
ID verification signal	Intelligent Key unit	BCM (CAN) IPDM E/R (CAN)	Inputs the ID verification signal via CAN communication
Engine status signal	ECM	BCM (CAN) TCM (CAN) IPDM E/R (CAN) Combination meter (CAN) ABS actuator and electric unit (CAN)	Inputs the engine status signal via CAN communication
Push-button ignition switch status signal	Intelligent Key unit	BCM (CAN)	Inputs the push-button ignition switch status signal via CAN communication
Brake pedal position switch	BCM	Intelligent Key unit (CAN)	Inputs the brake pedal position switch via CAN communication
CVT shift select signal	BCM	TCM (CAN)	Inputs the CVT shift select signal via CAN communication
Stop lamp switch signal	BCM	TCM (CAN) ABS actuator and electric unit (CAN)	Inputs the stop lamp switch signal via CAN communication
Door switch signal	BCM	Intelligent Key unit (CAN)	Inputs the door switch signal via CAN communication
Nissan Sentra Vehicle speed signal	ABS actuator and electric unit	BCM (CAN) TCM (CAN) IPDM E/R (CAN) Combination meter (CAN)	Inputs the engine status signal via CAN communication
Park/neutral position switch signal	ECM	BCM (CAN)	Inputs the park/neutral position switch signal via CAN communication
Clutch switch signal	BCM	IPDM E/R (CAN)	Inputs clutch switch signal via CAN communication

SYSTEM DESCRIPTION

• 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 Intelligent Key unit 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.

• Intelligent Key have ID (Key ID). It can perform the door lock/unlock operation and the push-button ignition switch operation when the registered Intelligent Key is carried.

• If the ID is successfully verified, when push-button ignition switch is pressed, the engine can be started.

• Up to 4 Intelligent Keys can be registered (Including the standard Intelligent Key) upon request from the customer.

PRECAUTIONS FOR INTELLIGENT KEY SYSTEM

The transponder (the chip for NATS ID verification) is integrated into the Intelligent Key. It is integrated into the mechanical key.) Therefore, ID verification cannot be performed by mechanical key only.

In that case, NATS ID verification can be performed when Intelligent Key backside is contacted to push-button ignition switch while brake pedal is depressed. If verification result is OK, engine can be started.

OPERATION WHEN INTELLIGENT KEY IS CARRIED

1. When the push-button ignition switch is pressed, the Intelligent Key unit 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 NATS ID signal to the Intelligent Key unit.

3. Intelligent Key unit receives the NATS ID signal verifies it with the registered ID.

4. When the ignition switch is placed to ON, Intelligent Key unit performs ID verification with the ECM. When the result is OK, engine start is permitted.

5. When ECM detects that the start engine conditions* are satisfied, it transmits a starter cut relay request signal to BCM.

6. When BCM receives a starter cut relay request signal from ECM, the starter cut relay is turned ON.

7. When starter cut relay is turned ON, IPDM E/R turns ON the starter relay and drives the starter motor.

8. When BCM receives an engine status signal from ECM, it turns the starter relay and starter cut relay OFF and stops cranking.

   CAUTION:

   When the Intelligent Key is carried outside of the Nissan Sentra vehicle (outside key antenna detection area) while the power supply is in the 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 Nissan Sentra 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, NATS ID verification between transponder in Intelligent Key and Intelligent Key unit 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

  • Nissan Sentra Vehicle speed

  M/T models

  • Brake pedal operation condition

  • Clutch pedal operation condition

  • Nissan Sentra Vehicle speed

Vehicle speed: less than 2.5 MPH (4 km/h)

Power supply position	Condition						Push-button ignition switch operation frequency
	CVT models		M/T models
	Selector lever	Brake pedal operation condition	Normal condition		Special condition
			Shift lever	Clutch pedal operation condition	Shift lever	Brake pedal operation condition
LOCK → ON	—	Not depressed	—	Not depressed	—	Not depressed	1
LOCK → ON → OFF	—	Not depressed	—	Not depressed	—	Not depressed	2
LOCK → START ON → START	P or N position	Depressed	—	Depressed	Neutral	Depressed	1
Engine is running → LOCK	—	—	—	—	—	—	1

Note:

If the Intelligent Key unit cannot detect that the Intelligent Key is in the Nissan Sentra vehicle, ignition switch can be placed OFF by the press and hold the push-button ignition switch for 2 seconds or more.

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

Power supply position	Condition						Push-button ignition switch operation frequency
	CVT models		M/T models
	Selector lever	Brake pedal operation condition	Normal condition		Special condition
			Shift lever	Clutch pedal operation condition	Shift lever	Brake pedal operation condition
Engine is running → OFF	—	—	—	—	—	—	Emergency stop operation
Engine stall return operation while driving	N position	Not depressed	—	Depressed	Neutral	—	1

Emergency stop operation

• Press and hold the push-button ignition switch for 2 seconds or more.

• Press the push-button ignition switch 3 times or more within 1.5 seconds.

Nissan Anti-Theft System

System Description

System Description

SYSTEM DIAGRAM

SIGNAL TRANSMISSION FUNCTION LIST

Signal name	Input	Output	Description
Inside key antenna signal	Intelligent Key unit	BCM (CAN) IPDM E/R (CAN)	Inputs the inside key signal antenna signal via CAN communication
ID verification signal	Intelligent Key unit	BCM (CAN) IPDM E/R (CAN)	Inputs the ID verification signal via CAN communication
Engine status signal	ECM	BCM (CAN) TCM (CAN) IPDM E/R (CAN) Combination meter (CAN) ABS actuator and electric unit (CAN)	Inputs the engine status signal via CAN communication
Push-button ignition switch status signal	Intelligent Key unit	BCM (CAN)	Inputs the push-button ignition switch status signal via CAN communication
Brake pedal position switch	BCM	Intelligent Key unit (CAN)	Inputs the brake pedal position switch via CAN communication
CVT shift select signal	BCM	TCM (CAN)	Inputs the CVT shift select signal via CAN communication
Stop lamp switch signal	BCM	TCM (CAN) ABS actuator and electric unit (CAN)	Inputs the stop lamp switch signal via CAN communication
Door switch signal	BCM	Intelligent Key unit (CAN)	Inputs the door switch signal via CAN communication

SYSTEM DESCRIPTION

• The NISSAN ANTI-THEFT SYSTEM (NATS) prevents the engine from being started by Intelligent Key whose ID is not registered to the Nissan Sentra vehicle (Intelligent Key unit). 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 NATS ID verification is performed between the transponder integrated with Intelligent Key and Intelligent Key unit via NATS antenna. 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.

• Up to 4 Intelligent Keys can be registered (including the standard ignition key) upon request from the owner.

• When replacing ECM, Intelligent Key unit or Intelligent Key, the specified procedure (Initialization and registration) using CONSULT is required.

PRECAUTIONS FOR KEY REGISTRATION

The ID registration is a procedure that erases the current NATS ID once, and then registers a new ID. Therefore before starting the registration operation, collect all registered Intelligent Keys from the customer.

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

1. When brake pedal is depressed while selector lever is in the P position, Intelligent Key unit activates NATS antenna that is located behind push-button ignition switch.

2. When Intelligent Key (transponder built-in) backside is contacted to push-button ignition switch, Intelligent Key unit starts NATS ID verification between Intelligent Key unit and Intelligent Key (transponder built-in) via NATS antenna.

3. When NATS ID verification result is OK, buzzer in combination meter sounds.

4. When the ignition switch is placed to ON, Intelligent Key unit performs ID verification with the ECM. When the result is OK, engine start is permitted.

5. BCM detects that the selector lever position and brake pedal operation condition.

6. When ECM detects that the start engine conditions* are satisfied, it transmits a starter cut relay request signal to BCM.

7. When BCM receives a starter cut relay request signal from ECM, the starter cut relay is turned ON.

8. When starter cut relay is turned ON, IPDM E/R turns ON the starter relay and drives the starter motor.

9. When BCM receives an engine status signal from ECM, it turns the starter relay and starter cut relay OFF and stops cranking.

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

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

  • Nissan Sentra Vehicle speed

  M/T models

  • Brake pedal operation condition

  • Clutch pedal operation condition

  • Nissan Sentra Vehicle speed

Vehicle speed: less than 2.5 MPH (4 km/h)

Power supply position	Condition						Push-button ignition switch operation frequency
	CVT models		M/T models
	Selector lever	Brake pedal operation condition	Normal condition		Special condition
			Shift lever	Clutch pedal operation condition	Shift lever	Brake pedal operation condition
LOCK → ON	—	Not depressed	—	Not depressed	—	Not depressed	1
LOCK → ON → OFF	—	Not depressed	—	Not depressed	—	Not depressed	2
LOCK → START ON → START	P or N position	Depressed	—	Depressed	Neutral	Depressed	1
Engine is running → LOCK	—	—	—	—	—	—	1

Note:

If the Intelligent Key unit cannot detect that the Intelligent Key is in the Nissan Sentra vehicle, ignition switch can be placed OFF by the press and hold the push-button ignition switch for 2 seconds or more.

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

Power supply position	Condition						Push-button ignition switch operation frequency
	CVT models		M/T models
	Selector lever	Brake pedal operation condition	Normal condition		Special condition
			Shift lever	Clutch pedal operation condition	Shift lever	Brake pedal operation condition
Engine is running → OFF	—	—	—	—	—	—	Emergency stop operation
Engine stall return operation while driving	N position	Not depressed	—	Depressed	Neutral	—	1

Emergency stop operation

• Press and hold the push-button ignition switch for 2 seconds or more.

• Press the push-button ignition switch 3 times or more within 1.5 seconds.

Vehicle Security System

System Description

System Description

SYSTEM DIAGRAM

SIGNAL TRANSMISSION FUNCTION LIST

Signal name	Input	Output	Description
Lock/unlock switch signal	BCM	IPDM E/R (CAN)	Inputs the lock/unlock switch signal via CAN communication
Each door switch signal	BCM	IPDM E/R (CAN)	Inputs the door switch via CAN communication
Hood switch signal	IPDM E/R	BCM (CAN)	Inputs the hood switch signal via CAN communication

SYSTEM DESCRIPTION

• The Nissan Sentra 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.

• 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.

  Priority	Function
  1	Theft warning alarm
  2	Panic alarm

THEFT WARNING ALARM

The theft warning alarm function activates horns and headlamps intermittently when BCM detects that any door is opened by unauthorized means while the system is in the ARMED state.

Operation Flow

No.	System state	Switching condition
1	DISARMED to PRE-ARMED	When all conditions of A and one condition of B is satisfied.	A	B
			Power supply position: OFF/LOCK All doors: Closed	All doors are locked by: LOCK button of Intelligent Key Door request switch
2	PRE-ARMED to ARMED	When all of the following conditions are satisfied for 30 seconds.	Power supply position: OFF/LOCK All doors: Locked
3	ARMED to ALARM	When one condition of A and one condition of B are satisfied.	A	B
			Intelligent Key: Not used	Any door: Open
4	DISARMED to PRE-RESET	No conditions
5	PRE-ARMED to PRE-RESET
6	ARMED to PRE-RESET
7	ALARM to PRE-RESET
8	PRE-RESET to DISARMED
9	PRE-RESET to PRE-ARMED
10	PRE-ARMED to DISARMED	When one of the following conditions is satisfied.	Power supply position: ACC/ON/CRANKING/RUN UNLOCK button of Intelligent Key: ON TRUNK button of Intelligent Key: ON Door request switch: ON Trunk opener switch: ON Any door: Open
11	ARMED to DISARMED	When one of the following conditions is satisfied.	Power supply position: ACC/ON/CRANKING/RUN UNLOCK button of Intelligent Key: ON Door request switch: ON Trunk opener switch: ON
12	ALARM to DISARMED
13	RE-ALARM	When one of the following conditions is satisfied after the ALARM operation is finished.	Any door: Open

Note:

• To lock/unlock all doors by operating remote controller button of Intelligent Key or door request switch, Intelligent Key must be within the detection area of outside key antenna. For details, refer to System Description.

• To open trunk by operating trunk opener switch, Intelligent Key must be within the detection area of outside key antenna. For details, refer to System Description.

DISARMED Phase

The Nissan Sentra vehicle security system is not set in the DISARMED phase. The vehicle security system stays in this phase while any door is open because it is assumed that the owner is inside or nearby the Nissan Sentra vehicle.

When the vehicle security system is reset, each phase switches to the DISARMED phase directly.

PRE-ARMED Phase

The PRE-ARMED phase is the transient state between the DISARMED phase and the ARMED phase. This phase is maintained for 30 seconds so that the owner can reset the setting due to a mis-operation. This phase switches to the ARMED phase when Nissan Sentra vehicle conditions are not changed for 30 seconds.

To reset the PRE-ARMED phase, refer to the switching condition of No. 10 in the table above.

ARMED Phase

The Nissan Sentra vehicle security system is set and BCM monitors all necessary inputs. If any door is opened without using Intelligent Key, Nissan Sentra vehicle security system switches to the ALARM phase.

To reset the ARMED phase, refer to the switching condition of No. 11 in the table above.

ALARM Phase

BCM transmits “Theft Warning Horn Request” signal and “High Beam Request” signal intermittently to IPDM E/R via CAN communication. In this phase, horns and headlamps are activated intermittently for approximately 50 seconds to warn that the Nissan Sentra vehicle is accessed by unauthorized means. ON/OFF timing of horns and headlamps are synchronized. After 50 seconds, the Nissan Sentra vehicle security system returns to the ARMED phase. At this time, if BCM still detects unauthorized access to the Nissan Sentra vehicle, the system is switched to the ALARM phase again. This RE-ALARM operation is carried out a maximum of 2 times.

To cancel the ALARM operation, refer to the switching condition of No. 12 in the table above.

Note:

If a battery terminal is disconnected during the ALARM phase, theft warning alarm stops. But when the battery terminal is reconnected, theft warning alarm is activated again.

PANIC ALARM

• The panic alarm function activates horns and headlamps intermittently when the owner presses the PANIC ALARM button of Intelligent Key outside the Nissan Sentra vehicle while the power supply position is OFF or LOCK.

• When Intelligent Key Unit receives panic alarm signal from Intelligent Key, BCM transmits “Theft Warning Horn Request” signal and “High Beam Request” signal intermittently to IPDM E/R via CAN communication. To prevent the activation due to mis-operation of Intelligent Key by owner, the panic alarm function is activated when Intelligent Key Unit receives the signal for 0.4 - 0.6 seconds.

• Panic alarm operation is maintained for 25 seconds.

• Panic alarm operation is cancelled when BCM receives one of the following signals:

  • LOCK button of Intelligent Key: ON

  • UNLOCK button of Intelligent Key: ON

  • PANIC ALARM button of Intelligent Key: Long pressed

  • Any door request switch: ON