Lexus NX manuals

Lexus NX: System Description

Lexus NX Service Manual / Vehicle Interior / Theft Deterrent / Keyless Entry / Theft Deterrent System / System Description

SYSTEM DESCRIPTION

  • The theft deterrent system can be set/canceled by locking/unlocking the doors performing any of the following operation:
    • Entry lock/unlock operation
    • Wireless lock/unlock operation*1
    • Key linked lock/unlock operation
    • By opening and closing the doors*2
      • *1: Using the remote door lock and unlock is also considered to be a wireless lock/unlock operation. (w/ Lexus Enform Remote)
      • *2: Only when setting the theft deterrent system.
  • The alarm function will be activated when someone attempts to forcibly unlock any of the doors or open any of the doors, engine hood or back door while the system is in the armed state.
  • In the alarm sounding state, the system illuminates the interior light and blinks the turn signal lights, the headlights and taillights. At the same time, the system sounds the vehicle horns and security horn assembly*1 or theft warning siren assembly*2 to deter break-in and theft as well as to warn people around the vehicle.

    HINT:

    The interior light is illuminated if the interior light door switch in the map light assembly is on.

    • *1: w/ Security Horn Assembly
    • *2: w/o Security Horn Assembly
  • The theft deterrent system has an active arming mode. There are 4 states in this mode; a disarmed state, an arming preparation state, an armed state and an alarm sounding state.

OUTLINE OF THEFT DETERRENT SYSTEM

(a) Disarmed state:

  • The alarm function is not operating.
  • The theft deterrent system is not operating.

(b) Arming preparation state:

  • The time until the system goes into the armed state.
  • The theft deterrent system is not operating.

(c) Armed state:

  • The theft deterrent system is operating.

(d) Alarm sounding state:

  • The alarm function is operating.

Alarm time:

approximately 57 seconds

Alarm Methods and Time

Alarm Method

Headlights

Blinking

Taillights

Blinking

Turn Signal Lights

Blinking

Interior Light

Illuminating

Vehicle Horns

Sounding

(approximately 0.4-second cycles)

Security Horn Assembly*1

Sounding

(approximately 0.4-second cycles)

Theft Warning Siren Assembly*2

Sounding

Alarm Time

Approximately 57 seconds
  • *1: w/ Security Horn Assembly
  • *2: w/o Security Horn Assembly

FUNCTION OF MAIN COMPONENTS

Component

Function

Security indicator light

Informs driver of theft deterrent system status.
  • Security horn assembly*1
  • Theft warning siren assembly*2

Sounds when attempted break-in or theft is detected.

Headlights

Blink when attempted break-in or theft is detected.

Turn signal lights

Blink when attempted break-in or theft is detected.

Interior light

Comes on when attempted break-in or theft is detected.

Vehicle horns

Sound when attempted break-in or theft is detected.
  • Front door courtesy light switch assembly (for LH/RH)
  • Rear door courtesy light switch assembly (for LH/RH)

Detects door status (open or closed).

Door unlock detection switch

Detects door status (locked or unlocked).

Engine hood courtesy switch (hood lock assembly)

Detects engine hood status (open or closed).

Back door courtesy light switch (back door lock assembly)

Detects back door status (open or closed).

Door unlock switch sub-assembly

Detects back door lock key cylinder status (unlocked).

Certification ECU (smart key ECU assembly)
  • Receives wireless door lock/unlock signal.
  • Receives entry door lock/unlock signal.
  • *1: w/ Security Horn Assembly
  • *2: w/o Security Horn Assembly

ACTIVE ARMING MODE

(a) Active arming mode:

This system operates as described in the diagram below when one of the items for each condition is met.

HINT:

  • The term "all doors" used in this section refers to the driver door, front passenger door, rear door LH and rear door RH and back door.
  • Using the remote door lock and unlock is also considered to be a wireless lock/unlock operation.*
    • *: w/ Lexus Enform Remote

Condition

Item

Condition [1]

In disarmed state 1, when the power switch is off, the system state is switched if the following condition is met:

  • With all doors and the engine hood closed, all doors are locked by wireless operation, the smart access system with push-button start or key linked power door lock operation.

In disarmed state 1, when the power switch is off, the engine hood is closed and all doors are locked, the system state is switched if the following condition is met:

  • The state changes from any of the doors being opened to all doors being closed.

Condition [2]
  • Allow approximately 30 seconds to elapse.

Condition [3]

One of the following conditions is met:

  • All doors are unlocked by wireless operation, the smart access system with push-button start or key linked power door lock operation.
  • Any door is unlocked.
  • Any door is opened.
  • The power switch is pushed.
  • The power switch is turned on (ACC) or on (IG). (Not using the remote start.*2)
  • The auxiliary battery is reconnected.

Condition [4]

One of the following conditions is met:

  • The engine hood is opened when the engine hood is closed.
  • Any door is opened when all doors are closed.
  • Any door is unlocked when all doors are locked.
  • When 5 seconds or more have elapsed after the power switch is pressed, the power source mode is changed from off to on (IG) without pressing the power switch. (Not using the remote start.*2)

Condition [5]

One of the following conditions is met:

  • The power switch is turned on (READY).
  • All doors are unlocked by wireless operation, the smart access system with push-button start or key linked power door lock operation.
  • The power switch is turned on (ACC) or on (IG) within 5 seconds after the power switch is pushed. (Not using the remote start.*2)
  • The power back door is opened with the wireless one motion function.*1

Condition [6]
  • After approximately 57 seconds, the alarm stops and the system returns to the armed state.

Condition [7]

One of the following conditions is met:

  • The open engine hood is closed with all the doors closed.
  • The power back door reservation lock is operated with the engine hood and a door other than the back door closed.*1

Condition [8]

One of the following conditions is met:

  • Any door is unlocked when all doors are locked.
  • Any door is opened.
  • The power switch is pushed.
  • The power switch is turned on (ACC) or on (IG). (Not using the remote start.*2)
  • The auxiliary battery is reconnected.
  • All doors are unlocked by wireless operation, the smart access system with push-button start or key linked power door lock operation.
  • The power back door is opened with the wireless one motion function.*1
  • During a close operation, the power back door reverses operation, stops partway or another door opens.*1

Condition [9]

In disarmed state 1, when the power switch is off, the system state is switched if the following condition is met:

  • With all doors closed and the engine hood open, all doors are locked by wireless operation, the smart access system with push-button start or key linked power door lock operation.

In disarmed state 1, when the power switch is off, the engine hood and back door are open and all doors are locked, the system state is switched if the following condition is met:

  • The state changes from any of the doors being opened to all doors being closed.

In disarmed state 1, when the power switch is off, the system state is switched if the following condition is met:

  • During a power back door close operation with all other doors closed, the doors are locked (power back door reservation lock) by wireless operation.*1

Condition [10]
  • The engine hood is opened.
  • *1: w/ Power Back Door System
  • *2: w/ Lexus Enform Remote

FORCED DOOR LOCK CONTROL

(a) The forced door lock control prevents the vehicle from being tampered with. Immediately after a door is unlocked (armed state), all doors are forced to lock by a forced door lock signal.

(1) If the following conditions are met, the forced door lock control is operated.

  • The theft deterrent system is in the armed state.
  • Any door is unlocked.

ALARM MEMORY FUNCTION

(a) If the alarm is set off (tampering is detected) while the theft deterrent system is in the armed state, it will be stored by the alarm memory function. Whenever the theft deterrent system is canceled, the alarm memory function causes the taillights to light up for 2 seconds in order to inform the user that the alarm has been set off.

(1) Condition that cause the taillights to light up for 2 seconds:

The theft deterrent system has entered the alarm sounding state (tampering has been detected) at least once.

HINT:

Active arming mode: See Active Arming Mode.

PANIC ALARM CONTROL

(a) Panic alarm control makes it possible to voluntarily set off the panic alarm by pressing the panic switch on the electrical key transmitter sub-assembly.

(1) Conditions that cause panic alarm control to set off the panic alarm:

The panic switch on the electrical key transmitter sub-assembly is pressed under the following conditions:

  • The power switch is off.
  • The theft deterrent system is not in the alarm sounding state.

(2) Conditions that cause the panic alarm control to shut off the alarm:

Any of the following conditions is met during panic alarm control operation:

  • The power switch is turned on (IG).
  • The panic switch is pressed again.
  • Any of the switches on the electrical key transmitter sub-assembly (lock/unlock/back door open) is pressed.
  • The panic alarm ends (approximately 57 seconds have elapsed).
  • The theft deterrent system switches to the alarm sounding state. Under this condition, the theft deterrent system controls the alarm rather than the panic alarm control. In order to cancel this alarm, refer to the theft deterrent system alarm sounding state cancellation procedure.

THEFT WARNING SIREN ASSEMBLY (w/o Security Horn Assembly)

(a) The theft warning siren assembly has an internal battery. If power to the theft warning siren assembly is interrupted or the communication line is open, the theft warning siren assembly detects it and sounds the alarm using the internal battery.

(b) The theft warning siren assembly has the following alarm controls: normal alarm control and open circuit alarm control. Under normal alarm control, the alarm sounds based on instructions from the main body ECU (multiplex network body ECU) whereas under open circuit alarm control, the theft warning siren assembly judges current security conditions and sounds the alarm by itself.

(1) Normal alarm control

The theft warning siren assembly sounds when the theft deterrent system is in the alarm sounding state and does not sound when the system is not in the alarm sounding state.

HINT:

If communication interruption between the theft warning siren assembly and main body ECU (multiplex network body ECU) continues for 70 seconds or more while the theft deterrent system is in the alarm sounding state, the theft warning siren assembly stops sounding.

(2) Open circuit alarm control

The theft warning siren assembly changes between the disarmed state and armed state in accordance with the theft deterrent system changes between the disarmed state and armed state. If the power source, ground or communication line is open while the theft warning siren assembly is in the armed state, the theft warning siren assembly sounds.

During the open circuit alarm sounding state, the theft warning siren assembly sounds intermittently for 28 seconds and then stops for 5 seconds. This pattern repeats a maximum of 9 times.

The intermittent sounding will stop when either condition is met:

1. The theft warning siren assembly changes to the disarmed state.

2. The open circuit is returned to normal.

SECURITY INDICATOR LIGHT OUTPUT

(a) According to the state of the theft deterrent system, the main body ECU (multiplex network body ECU) outputs a signal to turn the security indicator light on. However, some of the actual lighting conditions of the security indicator light are different from the output signals of the main body ECU (multiplex network body ECU).

Output

State of Theft Deterrent System

Security Indicator Light

Output Signal from Main Body ECU (Multiplex Network Body ECU)

Actual Lighting Condition

Disarmed state (1), (2)

Off
  • Off (Immobiliser system unset)
  • Blinking (Immobiliser system set)

Arming preparation state

On

On

Armed state

Off

Blinking

Alarm sounding state

On

On
Blinking Cycle

Time

Security Indicator Light

0.125 seconds

On

1.875 seconds

Off

HINT:

When the immobiliser system is set, the security indicator light blinks during both the disarmed state and the armed state due to output signals from the immobiliser system.

READ NEXT:

 How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT HINT: Use this procedure to troubleshoot the theft deterrent system. *: Use the Techstream. PROCEDURE 1. VEHICLE BROUGHT TO WORKSHOP NEXT 2

 Customize Parameters

CUSTOMIZE PARAMETERS INSTALL CUSTOMIZE THEFT DETERRENT SYSTEM HINT: The following items can be customized. NOTICE: When the customer requests a change in a function, first make sure that the functi

 Problem Symptoms Table

PROBLEM SYMPTOMS TABLE HINT: Troubleshooting of the theft deterrent system is based on the premise that the power door lock control system and the wireless door lock control system are operating no

SEE MORE:

 Fuel Level Sensor "A" Circuit Low (P0462,P0463)

DESCRIPTION Refer to DTC P0461. Click here DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory P0462 Fuel Level Sensor "A" Circuit Low Fuel sender gauge output resistance is less than 7 Ω for 30 seconds or more (1 trip detection logic). Open or short

 Removal

REMOVAL PROCEDURE 1. REMOVE NO. 1 SPEAKER OPENING COVER ASSEMBLY Click here 2. REMOVE AUTOMATIC LIGHT CONTROL SENSOR (a) Detach the 2 claws and remove the automatic light control sensor.

© 2016-2024 Copyright www.lexunx.com