2016 Pre-collision system?
Thread Starter
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2016 Pre-collision system?
I've read a ton of pre collision threads here where everyone says that the system will not actually stop the car..
then there's this video..
and this one
and this one..
Where it actually DOES fully stop the car..
So which one is it on the 2016 IS ? Anyone try this out with theirs yet?
then there's this video..
and this one
and this one..
Where it actually DOES fully stop the car..
So which one is it on the 2016 IS ? Anyone try this out with theirs yet?
Pit Crew
Joined: Oct 2015
Posts: 121
Likes: 17
From: TN
According to the Lexus website for the IS the PCS is available but from the description it says it is designed to "automatically begin braking before impact." It doesn't say it will stop the vehicle. The RX page states it is "able to automatically begin braking before impact, and can even brake the vehicle to a stop at speeds above 6 mph."
http://www.lexus.com/models/IS/safety
http://www.lexus.com/models/RX/safety
So, not sure if they are the same system or not. Would have to see what the actual manual states.
http://www.lexus.com/models/IS/safety
http://www.lexus.com/models/RX/safety
So, not sure if they are the same system or not. Would have to see what the actual manual states.
Thread Starter
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Okay, thanks for that info, looks like it won't stop us.. that's kinda lame, wonder if it can be updated with a SW update?
new question:
I am not convinced my pre collision system is working. I have pretty much come flying up behind my mothers parked car and waited to even touch the brakes till way closer than I'd think where I should get a warning.
On the 2014/2015/2016 - when do you get a warning?
One other thing is that when the PCS button (under the steering wheel) is pushed and is in the IN position I get a "PCS" light on the dash.
When it is OUT, no light. Could that mean that there's a problem? ie. which position is "ON" and which position is off?
The radar cruise control works just fine.
new question:
I am not convinced my pre collision system is working. I have pretty much come flying up behind my mothers parked car and waited to even touch the brakes till way closer than I'd think where I should get a warning.
On the 2014/2015/2016 - when do you get a warning?
One other thing is that when the PCS button (under the steering wheel) is pushed and is in the IN position I get a "PCS" light on the dash.
When it is OUT, no light. Could that mean that there's a problem? ie. which position is "ON" and which position is off?
The radar cruise control works just fine.
Pole Position
Joined: Mar 2015
Posts: 325
Likes: 11
From: Florida - Tampa Bay
Regarding the light on the dash and the PCS switch - when the light is lit it means the PCS is disabled.
Thread Starter
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Most likely it could be, but you bought a Toyota... uh, Lexus product, not a Tesla. Unlike Tesla you will have to buy a new car to get the "new car features" such as full-stop-PCS. This is called 'savvy marketing'.
Regarding the light on the dash and the PCS switch - when the light is lit it means the PCS is disabled.
Regarding the light on the dash and the PCS switch - when the light is lit it means the PCS is disabled.
I did have a car run a red light and go right across my path from right to left where I was doing 30 mph yesterday and I only missed him by inches.. I even had radar cruise control running at the time.. nobody was infront, just had it set at 30mph..
Pole Position
Joined: Mar 2015
Posts: 325
Likes: 11
From: Florida - Tampa Bay
Okay... so why isn't this thing yelling at me to BRAKE?
I did have a car run a red light and go right across my path from right to left where I was doing 30 mph yesterday and I only missed him by inches.. I even had radar cruise control running at the time.. nobody was infront, just had it set at 30mph..
I did have a car run a red light and go right across my path from right to left where I was doing 30 mph yesterday and I only missed him by inches.. I even had radar cruise control running at the time.. nobody was infront, just had it set at 30mph..
Last edited by LeapFrog; Nov 28, 2015 at 12:15 PM.
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Thread Starter
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How about my mothers parked car that I've gotten up to 15 mph (like in the videos above) and waited till the last second to hit the brakes...and nothing happens. I know it sounds stupid to mess around like this but I want to make SURE the system works because this was one thing that attracted me to the car. people generally drive like idiots around here and I'd like the car watching out for me.
I have felt no seatbelt tightening, no brake alert and for sure no brakes being pushed.
I see people complaining about it being too aggressive, either they drive like crazy people or my pcs isn't working like it should be because I can't get it to even warn me, forget about actually hitting the brakes!
Edit: I'm breaking out the owners manual now..
Last edited by J3ffrey; Nov 28, 2015 at 12:25 PM.
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Pole Position
Joined: Mar 2015
Posts: 325
Likes: 11
From: Florida - Tampa Bay
Edit: Just looked in the manual and the > 19 mph figure applies to the PCS brake assist. You should get pre-collision braking if PCS is enabled and the closing speed is > 10 mph. If that isn't happening then indeed maybe you have a fault in the system.
Last edited by LeapFrog; Nov 28, 2015 at 12:34 PM.
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Here's what the manual has to say just for future users:
I guess the people having problems with the system might just be lunatics behind the wheel 
(jk)... maybe it's a good thing I can't get it to warn me, I must just be too cautious? I have no lights on the dash.
■ The pre-collision system is operational when
The pre-collision system is enabled and the following conditions are met:
● Pre-collision warning:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 10 mph (15 km/h).
● Pre-collision brake assist:
• The VSC system is not disabled.
• Vehicle speed is greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
● Pre-collision braking:
• The VSC system is not disabled.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 10 mph (15 km/h).
● Suspension control (vehicles with Adaptive Variable Suspension System):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 19 mph (30 km/h).
■ Conditions that may trigger the system even if there is no danger of a collision
In any of the following situations where the frontal area of the radar sensor is interrupted,
the radar sensor may detect possibility of a frontal collision and the system may be activated.
● When passing by an oncoming vehicle in a curve or a turn to the right or the left.
● When rapidly approaching an obstacle ahead (e.g. preceding vehicle, toll gate barrier,
etc.)
● When there is a structural object (billboard, low ceiling, fluorescent light, etc.) above
the uphill road ahead
● When driving on a narrow road or through under a low overhead structure (bridge,
tunnel, fly-under, etc.)
● When driving on an uneven road surface
● When there is a metal object, bump, or protrusion on the road surface
● When vehicle’s front part is raised or lowered depending on loading conditions
● When the direction of radar sensor is misaligned by strong impact applied on an area
around the radar sensor, etc.
● When there is an obstacle (guard rail, etc.) by the roadside at the entrance to a curve
● When the front of your vehicle is pointing upwards (caused by putting a heavy load in
the trunk etc.)
When the system is activated in the situations described above, there is also a possibility
that the brakes may be applied with a force greater than normal.
258 4-5. Using the driving support systems
IS350/300/200t_U (OM53D18U)
■ Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may also be occasions
when the sensor cannot detect pedestrians, animals, bicycles, motorcycles, trees,
or snowdrifts.
■ Situations in which the pre-collision system does not function properly
The system may not function effectively in situations such as the following:
● On roads with sharp bends or uneven surfaces
● If a vehicle suddenly moves in front of your vehicle, such as at an intersection
● If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
● In inclement weather such as heavy rain, fog, snow or sand storms
● If the vehicle is skidding when VSC is not operating
● When your vehicle is steeply inclined
● When only part of your vehicle’s front end collides with, or contacts, a vehicle or object
in a frontal collision
● When the radar sensor moves off position due to its surrounding area being subjected
to a strong impact
● When an obstacle suddenly appears in front of the vehicle due to the steering wheel
being turned sharply or another cause
■ Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor contamination, etc. that results in the sensors
being unable to detect obstacles, the pre-collision system will be automatically disabled.
In this case, the system will not activate even if there is a collision possibility.
■ When there is a malfunction in the system or if the system is temporarily unusable
The pre-collision system warning light will flash and warning messages will be displayed.
The pre-collision system is enabled and the following conditions are met:
● Pre-collision warning:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 10 mph (15 km/h).
● Pre-collision brake assist:
• The VSC system is not disabled.
• Vehicle speed is greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
● Pre-collision braking:
• The VSC system is not disabled.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 10 mph (15 km/h).
● Suspension control (vehicles with Adaptive Variable Suspension System):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 19 mph (30 km/h).
■ Conditions that may trigger the system even if there is no danger of a collision
In any of the following situations where the frontal area of the radar sensor is interrupted,
the radar sensor may detect possibility of a frontal collision and the system may be activated.
● When passing by an oncoming vehicle in a curve or a turn to the right or the left.
● When rapidly approaching an obstacle ahead (e.g. preceding vehicle, toll gate barrier,
etc.)
● When there is a structural object (billboard, low ceiling, fluorescent light, etc.) above
the uphill road ahead
● When driving on a narrow road or through under a low overhead structure (bridge,
tunnel, fly-under, etc.)
● When driving on an uneven road surface
● When there is a metal object, bump, or protrusion on the road surface
● When vehicle’s front part is raised or lowered depending on loading conditions
● When the direction of radar sensor is misaligned by strong impact applied on an area
around the radar sensor, etc.
● When there is an obstacle (guard rail, etc.) by the roadside at the entrance to a curve
● When the front of your vehicle is pointing upwards (caused by putting a heavy load in
the trunk etc.)
When the system is activated in the situations described above, there is also a possibility
that the brakes may be applied with a force greater than normal.
258 4-5. Using the driving support systems
IS350/300/200t_U (OM53D18U)
■ Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may also be occasions
when the sensor cannot detect pedestrians, animals, bicycles, motorcycles, trees,
or snowdrifts.
■ Situations in which the pre-collision system does not function properly
The system may not function effectively in situations such as the following:
● On roads with sharp bends or uneven surfaces
● If a vehicle suddenly moves in front of your vehicle, such as at an intersection
● If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
● In inclement weather such as heavy rain, fog, snow or sand storms
● If the vehicle is skidding when VSC is not operating
● When your vehicle is steeply inclined
● When only part of your vehicle’s front end collides with, or contacts, a vehicle or object
in a frontal collision
● When the radar sensor moves off position due to its surrounding area being subjected
to a strong impact
● When an obstacle suddenly appears in front of the vehicle due to the steering wheel
being turned sharply or another cause
■ Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor contamination, etc. that results in the sensors
being unable to detect obstacles, the pre-collision system will be automatically disabled.
In this case, the system will not activate even if there is a collision possibility.
■ When there is a malfunction in the system or if the system is temporarily unusable
The pre-collision system warning light will flash and warning messages will be displayed.
■ Limitations of the pre-collision system
● The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Do not use the pre-collision system instead of normal braking operations under any
circumstances. This system will not prevent collisions or lessen damage or injuries in
all cases. Do not overly rely on this system. Failure to do so may cause an accident,
resulting in death or serious injury.
This system has been designed to help avoid and reduce the impact of collisions.
However, the system operates differently depending on the situation (P. 257,
258). As a result, the same level of performance may not be expected in all cases.
Also, the pre-collision brakes may not operate if the driver is depressing the brake
pedal or turning the steering wheel, as the system will determine such conditions as
collision avoidance operations.
● As the pre-collision system is designed to assist the driver in safe driving, it may operate
under sporty driving conditions, which may cause an accident. For this reason
under sporty driving conditions, it is recommended that this system be disabled by
using the PCS OFF switch.
■ Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
● Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
● Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may become inaccurate or
malfunction. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by your Lexus dealer.
● Do not disassemble the sensor.
● Do not attach accessories or stickers to the sensor, grille cover or surrounding area.
● Do not modify or paint the sensor and grille cover.
● If the radar sensor needs to be replaced, contact your Lexus dealer.
● The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Do not use the pre-collision system instead of normal braking operations under any
circumstances. This system will not prevent collisions or lessen damage or injuries in
all cases. Do not overly rely on this system. Failure to do so may cause an accident,
resulting in death or serious injury.
This system has been designed to help avoid and reduce the impact of collisions.
However, the system operates differently depending on the situation (P. 257,
258). As a result, the same level of performance may not be expected in all cases.
Also, the pre-collision brakes may not operate if the driver is depressing the brake
pedal or turning the steering wheel, as the system will determine such conditions as
collision avoidance operations.
● As the pre-collision system is designed to assist the driver in safe driving, it may operate
under sporty driving conditions, which may cause an accident. For this reason
under sporty driving conditions, it is recommended that this system be disabled by
using the PCS OFF switch.
■ Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
● Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
● Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may become inaccurate or
malfunction. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by your Lexus dealer.
● Do not disassemble the sensor.
● Do not attach accessories or stickers to the sensor, grille cover or surrounding area.
● Do not modify or paint the sensor and grille cover.
● If the radar sensor needs to be replaced, contact your Lexus dealer.
■ Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-collision system is intended to assist the
driver in avoiding collisions through the process of LOOK-JUDGE-ACT. There are
limits to the degree of assistance the system can provide, so please keep in mind the
following important points.
● Assisting the driver in watching the road
The pre-collision system is only able to detect obstacles directly in front of the vehicle,
and only within a limited range. It is not a mechanism that allows careless or inattentive
driving, and it is not a system that can assist the driver in low-visibility conditions. It
is still necessary for the driver to pay close attention to the vehicle’s surroundings.
● Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data available to
the pre-collision system is that from obstacles it has detected directly in front of the
vehicle. Therefore, it is absolutely necessary for the driver to remain vigilant and to
determine whether or not there is a possibility of collision in any given situation.
● Assisting the driver in taking action
The pre-collision system's braking assist feature is designed to help reduce the severity
of a collision, and so only acts when the system has judged that a collision is
unavoidable. This system is not capable of automatically avoiding a collision or bringing
the vehicle to a stop safely without appropriate operations performed by the
driver. For this reason, when encountering a dangerous situation the driver must take
direct and immediate action in order to ensure the safety of all involved.
By means of alarms and brake control, the pre-collision system is intended to assist the
driver in avoiding collisions through the process of LOOK-JUDGE-ACT. There are
limits to the degree of assistance the system can provide, so please keep in mind the
following important points.
● Assisting the driver in watching the road
The pre-collision system is only able to detect obstacles directly in front of the vehicle,
and only within a limited range. It is not a mechanism that allows careless or inattentive
driving, and it is not a system that can assist the driver in low-visibility conditions. It
is still necessary for the driver to pay close attention to the vehicle’s surroundings.
● Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data available to
the pre-collision system is that from obstacles it has detected directly in front of the
vehicle. Therefore, it is absolutely necessary for the driver to remain vigilant and to
determine whether or not there is a possibility of collision in any given situation.
● Assisting the driver in taking action
The pre-collision system's braking assist feature is designed to help reduce the severity
of a collision, and so only acts when the system has judged that a collision is
unavoidable. This system is not capable of automatically avoiding a collision or bringing
the vehicle to a stop safely without appropriate operations performed by the
driver. For this reason, when encountering a dangerous situation the driver must take
direct and immediate action in order to ensure the safety of all involved.
(jk)... maybe it's a good thing I can't get it to warn me, I must just be too cautious? I have no lights on the dash.
Pole Position
Joined: Mar 2015
Posts: 325
Likes: 11
From: Florida - Tampa Bay
Could be - the first time the system braked for me I was driving down a street looking for a parking place on the opposite side of the street (so my head was turned to the left). The car in front of me stopped abruptly and the system applied the brakes and beeped at me - it sure got my attention and probably saved me from a crash.
Advanced
Joined: Jun 2009
Posts: 643
Likes: 52
From: Alberta
In my experience, the system will warn you just before a collision is imminent and brake only when a collision is unavoidable. I prefer the system to operate this way because it probably reduces false alerts. There's also been reports on CL community where the system has inadvertently braked where it shouldn't have.
If you want to test the system (not recommended), find somewhere that has a guardrail or metal barricade at the end of lane (like a merge lane). There is a particular spot I drive by often and I can always get it warn me here if I don't shift lanes sooner.
Keep in mind, this is a reactive safety feature on the IS that isn't intended to prevent a collision, but rather to mitigate the effects of a severe collision. i.e., it may save your life, but your legs may still be broken.
If you want to test the system (not recommended), find somewhere that has a guardrail or metal barricade at the end of lane (like a merge lane). There is a particular spot I drive by often and I can always get it warn me here if I don't shift lanes sooner.
Keep in mind, this is a reactive safety feature on the IS that isn't intended to prevent a collision, but rather to mitigate the effects of a severe collision. i.e., it may save your life, but your legs may still be broken.
Thread Starter
Intermediate
Joined: Jan 2012
Posts: 489
Likes: 0
Thanks,
I actually did get it to work so it's cool.
What my sister and I did was take her car (beater) and got up over 27 mph (where adaptive cruise control starts working). Her max speed was 35.
She slowed down fast and stopped... the car immediately started to slow and hit the brakes hard, then as we went under 27 it beeped twice to let me know it was going to release the brakes and I was on my own, but it didn't seem to actually release the brakes all the way, instead I got the BRAKE warning light and then I hit the brakes.. had plenty of time to avoid collision.
So that's good. I hope to only see that warning light when it's really needed again.
On a side note I think the radar cruise control is actually helping me to be a better driver, at least on the highway. For some reason when you set the thing at 70 (with three bars) and you don't have to sit there and worry about the gas pedal it's a less stressful drive. I can't wait for a self driving lexus to hit the road!
I actually did get it to work so it's cool.
What my sister and I did was take her car (beater) and got up over 27 mph (where adaptive cruise control starts working). Her max speed was 35.
She slowed down fast and stopped... the car immediately started to slow and hit the brakes hard, then as we went under 27 it beeped twice to let me know it was going to release the brakes and I was on my own, but it didn't seem to actually release the brakes all the way, instead I got the BRAKE warning light and then I hit the brakes.. had plenty of time to avoid collision.
So that's good.
I hope to only see that warning light when it's really needed again. On a side note I think the radar cruise control is actually helping me to be a better driver, at least on the highway. For some reason when you set the thing at 70 (with three bars) and you don't have to sit there and worry about the gas pedal it's a less stressful drive. I can't wait for a self driving lexus to hit the road!
Driver School Candidate
Joined: May 2016
Posts: 3
Likes: 0
From: CA
I have piled up boxes and hung cushions, and driven my car directly into them and my car didn't break at all. I did the experiment twice, exactly the same both times. One time I got the brake warning and beeping but no breaks, and the next time nothing. I hit hit the boxes both times. I went to the service center at the dealership and told them the problem and they said they had no way to diagnose the problem without a light coming on to indicate that I have a problem. So what do I do?
I guess the people having problems with the system might just be lunatics behind the wheel (jk)... maybe it's a good thing I can't get it to warn me, I must just be too cautious? I have no lights on the dash.[/QUOTE]
I guess the people having problems with the system might just be lunatics behind the wheel
(jk)... maybe it's a good thing I can't get it to warn me, I must just be too cautious? I have no lights on the dash.[/QUOTE]
Driver School Candidate
Joined: May 2016
Posts: 3
Likes: 0
From: CA
Pcs....not breaking
I have piled up boxes and hung cushions, and driven my car directly into them and my car didn't break at all. I did the experiment twice, exactly the same both times. One time I got the brake warning and beeping but no breaks, and the next time nothing. I hit hit the boxes both times. I went to the service center at the dealership and told them the problem and they said they had no way to diagnose the problem without a light coming on to indicate that I have a problem. So what do I do?
I guess the people having problems with the system might just be lunatics behind the wheel (jk)... maybe it's a good thing I can't get it to warn me, I must just be too cautious? I have no lights on the dash.[/QUOTE]
I guess the people having problems with the system might just be lunatics behind the wheel
(jk)... maybe it's a good thing I can't get it to warn me, I must just be too cautious? I have no lights on the dash.[/QUOTE]