Lexus NX: Precaution

Lexus NX Service Manual / Vehicle Interior / Pre-collision / Pre-collision System / Precaution

PRECAUTION

PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE AUXILIARY BATTERY TERMINAL

NOTICE:

When disconnecting the cable from the negative (-) auxiliary battery terminal, initialize the some systems after the cable is reconnected.
Click here
If the auxiliary battery has been discharged and charged or the cable has been disconnected and reconnected to the negative (-) auxiliary battery terminal, perform Steering Sensor Zero Point Calibration.
Click here

CAUTION:

When driving on public roads, obey all speed limits and traffic laws.

PRE-COLLISION SYSTEM OPERATION CONDITIONS

(a) The pre-collision system is enabled and the system determines that the possibility of a frontal collision with a detected object is high. Each function is operational at the following speed

Pre-collision warning

Operation target	Vehicle speed	Relative speed between your vehicle and object
Vehicles	Approximately 10 to 180 km/h (7 to 110 mph)	Approximately 10 to 180 km/h (7 to 110 mph)
Bicyclists and pedestrians*	Approximately 10 to 80 km/h (7 to 50 mph)	Approximately 10 to 80 km/h (7 to 50 mph)

Pre-collision brake assist

Operation target	Vehicle speed	Relative speed between your vehicle and object
Vehicles	Approximately 30 to 180 km/h (20 to 110 mph)	Approximately 30 to 180 km/h (20 to 110 mph)
Bicyclists and pedestrians*	Approximately 30 to 80 km/h (20 to 50 mph)	Approximately 30 to 80 km/h (20 to 50 mph)

Pre-collision braking

Operation target	Vehicle speed	Relative speed between your vehicle and object
Vehicles	Approximately 10 to 180 km/h (7 to 110 mph)	Approximately 10 to 180 km/h (7 to 110 mph)
Bicyclists and pedestrians*	Approximately 10 to 80 km/h (7 to 50 mph)	Approximately 10 to 80 km/h (7 to 50 mph)

*: Operation targets differ depending on the destination.

(b) Cancelation of the pre-collision braking

(1) If either of the following occur while the pre-collision braking function is operating, it will be canceled:

The accelerator pedal is depressed strongly
The steering wheel is turned sharply or abruptly

HINT:

When the vehicle is stopped due to operation of pre-collision braking, pre-collision braking operation will be canceled approximately 2 seconds after the vehicle has stopped.

If an auxiliary battery terminal has been disconnected and reconnected and then the vehicle has not been driven for a certain amount of time
If the shift lever is in R
When the VSC OFF indicator is illuminated (only the pre-collision warning function will be operational)
When PCS warning light is illuminated

HANDLING PRECAUTION FOR PRE-COLLISION SYSTEM

(a) Conditions under which the system may operate even if there is no possibility of a collision.

In some situations such as the following, the system may determine that there is a possibility of a frontal collision and operate.

When passing a detectable object, etc.
When changing lanes while overtaking a detectable object, etc.
When approaching a detectable object in an adjacent lane or on the roadside, such as when changing the course of travel or driving on a winding road
When rapidly closing on a detectable object, etc.
When approaching objects on the roadside, such as detectable objects, guardrails, utility poles, trees, or walls
When there is a detectable object or other object by the roadside at the entrance of a curve
When there are patterns or paint in front of your vehicle that may be mistaken for a detectable object
When the front of your vehicle is hit by water, snow, dust, etc.
When overtaking a detectable object that is changing lanes or making a right/left turn
When passing a detectable object in an oncoming lane that is stopped to make a right/left turn
When a detectable object approaches very close and then stops before entering the path of your vehicle
If the front of your vehicle is raised or lowered, such as when on an uneven or undulating road surface
When driving on a road surrounded by a structure, such as in a tunnel or on an iron bridge
When there is a metal object (manhole cover, steel plate, etc.), steps, or a protrusion in front of your vehicle
When passing under an object (road sign, billboard, etc.)
When approaching an electric toll gate barrier, parking area barrier, or other barrier that opens and closes
When using an automatic car wash
When driving through or under objects that may contact your vehicle, such as thick grass, tree branches, or a banner
When driving through steam or smoke
When driving near an object that reflects radio waves, such as a large truck or guardrail
When driving near a TV tower, broadcasting station, electric power plant, or other location where strong radio waves or electrical noise may be present

(b) Situations in which the system may not operate properly

In some situations such as the following, an object may not be detected by the millimeter wave radar sensor assembly and forward recognition camera, preventing the system from operating properly:

When a detectable object is approaching your vehicle
When your vehicle or a detectable object is wobbling
If a detectable object makes an abrupt maneuver (such as sudden swerving, acceleration or deceleration)
When your vehicle approaches a detectable object rapidly
When a detectable object is not directly in front of the vehicle
When a detectable object is near a wall, fence, guardrail, manhole cover, vehicle, steel plate on the road, etc.
When a detectable object is under a structure
When part of a detectable object is hidden by an object, such as large baggage, an umbrella, or guardrail
When multiple detectable objects are close together
If the sun or other light is shining directly on a detectable object
When a detectable object is a shade of white and looks extremely bright
When a detectable object appears to be nearly the same color or brightness as its surroundings
If a detectable object cuts or suddenly emerges in front of the vehicle
When the front of the vehicle is hit by water, snow, dust, etc.
When a very bright light ahead, such as the sun or the headlights of oncoming traffic, shines directly into the forward recognition camera
When approaching the side or front of a vehicle ahead
If a vehicle ahead is a bicycle or motorcycle
If a vehicle ahead is narrow, such as a personal mobility vehicle
If a preceding vehicle has a small rear end, such as an unloaded truck
If a preceding vehicle has a low rear end, such as a low bed trailer
If a vehicle ahead has extremely high ground clearance
If a vehicle ahead is carrying a load which protrudes past its rear bumper
If a vehicle ahead is irregularly shaped, such as a tractor or side car
If a vehicle ahead is a child sized bicycle, a bicycle that is carrying a large load, a bicycle ridden by more than one person, or a uniquely shaped bicycle (bicycle with a child seat, tandem bicycle, etc.)
If a pedestrian/or the riding height of a bicyclist ahead is shorter than approximately 1 m (3.2 ft.) or taller than approximately 2 m (6.5 ft.)
If a pedestrian/bicyclist is wearing oversized clothing (a rain coat, long skirt, etc.), making their silhouette obscure
If a pedestrian is bending forward or squatting or bicyclist is bending forward
If a pedestrian/bicyclist is moving fast
If a pedestrian is pushing a stroller, wheelchair, bicycle or other vehicle
When driving in inclement weather such as heavy rain, fog, snow or a sandstorm
When driving through steam or smoke
When the surrounding area is dim, such as at dawn or dusk, or while at night or in a tunnel, making a detectable object appear to be nearly the same color as its surroundings
When driving in a place where the surrounding brightness changes suddenly, such as at the entrance or exit of a tunnel
After the hybrid system has started the vehicle has not been driven for a certain amount of time
While making a left/right turn and for a few seconds after making a left/right turn
While driving on a curve and for a few seconds after driving on a curve
If your vehicle is skidding
If the front of the vehicle is raised or lowered
If the wheels are misaligned
If a wiper blade is blocking the forward recognition camera
The vehicle is being driven at extremely high speeds
When driving on a hill
If the radar sensor or forward recognition camera is misaligned

(c) In some situations such as the following, sufficient braking force may not be obtained, preventing the system from performing properly:

If the braking functions cannot operate to their full extent, such as when the brake parts are extremely cold, extremely hot, or wet
If the vehicle is not properly maintained (brakes or tires are excessively worn, improper tire inflation pressure, etc.)
When the vehicle is being driven on a gravel road or other slippery surface

(d) If VSC is disabled

If VSC is disabled, the pre-collision brake assist and pre-collision braking functions are also disabled.
The PCS warning light will turn on and "VSC Turned Off Pre-Collision Brake System Unavailable" will be displayed on the multi-information display.

PRECAUTION BEFORE SERVICING

(a) When to disable the pre-collision system

In the following situations, disable the system, as it may not operate properly, possibly leading to an accident resulting in death or serious injury:

When the vehicle is being towed
When the vehicle is towing another vehicle
When transporting the vehicle via truck, boat, train or similar means of transportation
When the vehicle is raised on a lift with the hybrid system on and the tires are allowed to rotate freely
When inspecting the vehicle using a drum tester such as a chassis dynamometer or speedometer tester, or when using an on vehicle wheel balancer
When a strong impact is applied to the front bumper or front grille, due to an accident or other reasons
If the vehicle cannot be driven in a stable manner, such as when the vehicle has been in an accident or is malfunctioning
When the vehicle is driven in a sporty manner or off-road
When the tires are not properly inflated
When the tires are very worn
When tires of a size other than specified are installed
When tire chains are installed
When a compact spare tire or an emergency tire puncture repair kit is used
If equipment (snow plow, etc.) that may obstruct the radar sensor or forward recognition camera is temporarily installed to the vehicle

TROUBLESHOOTING PRECAUTIONS

(a) If a terminal contact malfunction or part installation problem occurs, removal and reinstallation of the suspected part may return the system to normal. However, be aware that the normal condition may only be temporary.

(b) Before disconnecting connectors or removing/installing parts, determine the malfunctioning area by checking and writing down the vehicle conditions (output DTCs, etc.) at the time the malfunction occurred.

(c) Be sure to check for DTCs related to other systems. The pre-collision system may be influenced by malfunctions in other systems.

(d) The pre-collision system uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.

HANDLING PRECAUTIONS

(a) When removing and installing ECUs, sensors, switches or other pre-collision system related parts, perform the following:

Make sure that the engine switch is off unless otherwise specified in the procedure.
After removal/installation, check for DTCs and confirm that a normal system code is output.

REPLACEMENT PRECAUTIONS

(a) MILLIMETER WAVE RADAR SENSOR ASSEMBLY:

(1) When replacing the millimeter wave radar sensor assembly, always replace it with a new one. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

(2) If the millimeter wave radar sensor assembly has been replaced with a new one, be sure to perform Front Beam Axis Adjustment.

Click here

(b) FORWARD RECOGNITION CAMERA:

(1) When the forward recognition camera is replaced with a new one or the windshield glass is replaced or removed/installed, make sure to perform beam axis adjustment for the forward recognition camera and clear the vehicle control history for each system.

HINT:

Forward recognition camera adjustment can be performed by using either "One Time Recognition" or "Sequential Recognition".

One Time Recognition:

Click here

Sequential Recognition:

Click here

(2) When replacing the forward recognition camera, always replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

(3) Do not dirty or damage the lens when replacing the forward recognition camera.

(4) Do not use a forward recognition camera if it has been dropped or subjected to any strong impact.

(1) When replacing the windshield glass of a vehicle equipped with a forward recognition camera, make sure to use a Lexus genuine part. If a non-Lexus genuine part is used, the forward recognition camera may not be able to be installed due to a missing bracket or the pre-collision system may not operate properly due to a difference in the transmissivity or black ceramic border.

(2) Do not attach stickers, including transparent stickers, or other items to the outer side of the windshield glass assembly within the area in front of the forward recognition camera.

SEE MORE:

Reassembly

REASSEMBLY PROCEDURE 1. INSTALL STIFFENING CRANKCASE RING PIN NOTICE: It is not necessary to remove the ring pin unless it is being replaced. *a Protrusion Height (a) Using a plastic-faced hammer, tap in 2 new ring pins until they stop. Standard protrusion height: 4.3 to 5.3 mm (0.169 to 0

Dtc Check / Clear

DTC CHECK / CLEAR DTC CHECK USING TECHSTREAM (a) Connect the Techstream to the DLC3. (b) Turn the power switch on (IG). (c) Turn the Techstream on. (d) Enter the following menus: Body Electrical / Air Conditioner / Trouble Codes. (e) Check for DTCs. Click here Body Electrical > Air Conditioner &

Lexus NX: Precaution

READ NEXT:

Parts Location

System Diagram

How To Proceed With Troubleshooting

SEE MORE:

Reassembly

Dtc Check / Clear