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System Description

SYSTEM DIAGRAM 

GNSDB148901Courtesy of NISSAN NORTH AMERICA, INC.

BCM INPUT/OUTPUT SIGNAL CHART 

Input Signal Item 

Transmit unit Signal name
ECM CAN communication
  • ID verification signal
  • Engine status signal
IPDM E/R
  • Push-button ignition switch status signal
  • Starter relay status signal
  • Starter control relay signal
  • Detention switch signal
  • Interlock/PNP switch signal
Combination meter Vehicle speed signal
ABS actuator and electric unit (control unit) Vehicle speed signal
TCM Shift position signal
TCU Engine start request signal
Remote keyless entry receiver Key ID signal
Push-button ignition switch Push switch signal
Each door switch Door switch signal
Stop lamp switch Stop lamp switch signal
A/T shift selector (detention switch) P position signal
TCM P/N position signal

Output Signal Item 

Reception unit Signal name
Combination meter CAN communication Key warning lamp signal
ECM ID verification signal
Inside key antenna Inside key antenna signal

SYSTEM DESCRIPTION 

PRECAUTIONS FOR INTELLIGENT KEY SYSTEM 

The transponder (the chip for NATS ID verification) is integrated into the Intelligent Key. (For the conventional models, 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 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 "Intelligent Key system malfunction display" display on information display in combination meter. 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 motor 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, 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,
    • Brake pedal operation condition
    • Selector lever position
    • Vehicle speed

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

Power supply position Condition Push-button ignition switch operation frequency
Selector lever Brake pedal operation condition
OFF → ACC - Not depressed 1
OFF → ACC → ON - Not depressed 2
OFF → ACC → ON → OFF - Not depressed 3
OFF → START
ACC → START
ON → START
P or N position Depressed 1
Engine is running → OFF - - 1

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

Power supply position Condition Push-button ignition switch operation frequency
Selector lever Brake pedal operation condition
Engine is running → ACC - - Emergency stop operation
Engine stall return operation while driving N position Not depressed 1

Emergency stop operation

Emergency engine stop is activated when any of the following operation is performed.

REMOTE ENGINE START FUNCTION 

Remote engine start function enables engine to be started from vehicle outside by operating REMOTE ENGINE START button of Intelligent Key or mobile phone.

In the same way as the Intelligent Key, the engine can be started by operating a cellular phone using the Telematics system function. For details: Refer to System Description .

Engine Start Procedures 

The following operation enables the engine to be started.

Engine does not start while the vehicle is in the following status.

Engine Stop Procedures 

The following operation enables the engine to be stopped.

Engine stops when the vehicle status changes to the following status

NOTE: While engine is in operation by Intelligent Key, engine operation time can be extended for 10 minutes. To extend engine operation time, press LOCK button of Intelligent Key, and then within 5 seconds, press and hold REMOTE ENGINE START button of Intelligent Key for 2 seconds or more.

Operation Area 

The engine can be started when the vehicle is under the following conditions.