Hi guys,

well having owned my ISF for nearly 2 months now I've had some time to see how certain things work and wanted to ask this question:

How many of you drive your car with PCS system on?


In the past while driving around with my wife I would switch it off because she's pregnant and I didn't want to take the chance of the PCS system kicking in for no reason (there are many reasons why it could do this if you read the manual it's actually scary because as per the owners manual the PCS system can kick in pretty much for no reason)

So anyway lately it's been only me driving the car with no passengers so I've had the PCS system on.

Today while driving to work I changed lanes and there was a car in front of my but I already knew that and wanted to switch over 2 lanes.

After making the first lane change and going to the second lane the PCS kicked in and either applied some brake or let off the gas which reduced my car's speed and I nearly got rear ended by a van driving behind me

So Now I'm going to be switching this stupid system off when driving in any "spirited" form.

The only annoying thing is the damn PCS sign stays switched on the dash which is annoying but livable.


Any thoughts? recommendations? or how do you guys deal with it?

 

Maybe it's bc I have an 11, but I have no idea what PCS is...

 

PCS = Pre-collision System. I have a '12 and it's not on mine either. I took a quick look on the Canadian Lexus website under the IS F and there's no mention of it anywhere under available safety features. Maybe it's available in certain markets. Don't know.

 

I have never heard of it myself also.

 

I have an 11 in Cali - I don't have a PCS - OP you r in Saudi Arabia right?

 

Typically PCS is specially ordered and is rolled in with the dynamic cruise control. I honestly don't think it's worth the near two grand extra for it simply because I don't trust technology like that. Blind Spot Monitor is an exception I love but not available on 2IS based IS/F/C. Honestly nothing beats good driving, smart thinking and trust your instinct. Seriously just go to a track driving school for a day and learn the car and its limits. The cost will still be less than buying PCS

 

I do have it on and i've a 2008 IS-F. I am not sure if you can turn it off completely but for me it works together with the cruise control radar which keeps distance with the car in front. If the car in front gets too close then the PCS brakes. But when not using cruise control it doesn't kick in besides the fact that if you are too close to a car it starts beeping.

I've always turned the radar off when using cruise control and therefore the PCS never kicks in.

The PCS sensor itself is inside the Lexus badge in the front. I found this out by accident when driving in heavy snow and the front of my car was like the side of a snowy mountain. The dashboard showed the yellow PCS thing and i looked it up in the manual.

 

No PCS here.

I'm more concerned with all the California drivers who text and drive. I usually change lanes when I spot them in my RVM, and trust me, they are easy to spot. (They keep looking down as they drive.....)

And people wonder why the insurance rates here are so high.............

 

Yes living in Saudi Arabia

I totally agree, I know it's hard to believe but with all the oil and money here there isn't a single track or 1/4 mile strip anywhere on the west coast of Saudi Arabia.

That's why we have loads of retards driving around like Muppets on the streets.

Finally at least someone else has it.

Over here you can't order options on cars, you can just buy what's available.

Now for the stealers to jack up the price and inflate it as much as possible they pretty much add all options available so the car becomes expensive and sell it with a load of profit.

Pretty retarded but then again all car dealerships in this country are thieving crooks

 

Answer:
I have a '08 ISF and it has kicked on with me before. I believe the problem is if you have your cruise control ON and SET and if you accelerate the cruise control is still engaged and if you let off the throttle the cruising speed will resume, so the PCS will activate automatically if you accelerate (by using the foot throttle) and come up on the car in front of you too quickly. I only know this because I travel a lot of two lane roads. Unlike when you apply the breaks the cruise control will disengage the speed that has been set.

There is nothing wrong with the car it actually does its job very well you just need to know this information that is not in the manual. Trust me I freaked out the first time this happened to me.
It works as if you may have the cruise control on and you fall asleep and press the accelerator or if the car in front slows dramatically...
I hope this helps

 

Thanks for the info Nerd42,


But I am 100% sure that the cruise control was off because I never use it and no displays on the dash were there to say it's on. But the PCS system was on and active, I can disengage it but I usually keep it on because it has never acted like this before.

I believe the main reason the PCS system kicked in is because it thought that I was not paying attention to the car in front of my while changing lanes and so applied the brakes.

I'll just make sure it's off next time. The only annoying thing is I cannot switch it off while driving, it'll only allow me to switch it off when I slow down to a stop.

Plus as soon as PCS is off I get this retarded display on my dash that keeps on telling me PCS is off.

 

I used to have it on all the time, back when I owned an IS350 between 2006 - 2010.

Did you have cruise control on (because the pre-collision portion of it will do things like beep in hazardous situations, but that's different than the radar cruise)?

It sounds like it was just adjusting speed to control distance (depending on how many lengths you've set), which is normal-- otherwise this never really happened to me. If I understand what happened correctly, it's not too different than lane changes I've frequently made, and I want to say it should at least detect the rate of speed of the car in front of you, as well as the steering angle/throttle input.

Did the system beep at all while slowing? If so, then it determined that an impact was possible and that you should pay attention, which is normal and may be chalked up to a misunderstanding of the system.

Not sure how "spirited" spirited is, but it may lead to your answer. I would only use the cruise portion of it when actually cruising, and in light or no traffic. It worked predictably and rather well over the course of four years, but in any type of driving where I expected to change lanes more often, especially in any type of congestion, it didn't make sense to have it on. This also applies to using it in the rain or where there are many turns.

Though they exist as part of the same package, there are some interesting distinctions between the actions of the radar-cruise and the pre-collision system. In another example, the latter will retract your seatbelts preemptively, when it predicts an impact is imminent. Did this happen?

Ultimately, I'd say the system worked very well and though it takes some getting used to, I wouldn't fear it. Above all, it's not so different than normal cruise control, meaning you should still pay attention, only it intervenes. If I were cruising around at 65 and came upon a vehicle in another lane, I'd control my speed, just the same, if I were trying to maintain a given distance.

 

Thanks for the input Shinobi,

I didn't have cruise control on, I'm actually still trying to figure out how to switch it on.

The system did beep before closing down, I actually just thought about it, While I was changing lanes the car in front might have slowed down as I was trying to cross into a 3rd lane. so that would explain it kicking in.

But I agree I'll be switching it off when in congested areas as it'll just be a pain.

on a side note I hope this PCS system doesn't add too much to the overall weight of the car ....I'd rather not have it if I have the option.

 

IIRC, it should activate the same as when you use regular cruise control. Turn the system on, reach a given speed, and set it. From there, you can adjust speed in increments, up or down.

The main difference is that you will also be able to set the following distance, and the system will show a dash indicator for when it detects an object in front of it (when following, distance gets priority over speed. You're limited by the speed of the vehicle in front of you).

That could be it, but if you didn't have dynamic cruise control on by mistake, then I'm unsure (closing down?). IIRC, if you aren't cruising, then there is no real reason for it to warn you about closing-distance, unless it's a near-crash situation (but again, the seat-belts would've also preemptively restrained you, and that's usually initiated by some type of threshold braking...you'll definitely know the difference <-- sometimes that would trigger unnecessarily).

No clue as to how much it adds. I know the unit sits a bit behind the emblem within the bumper cover, but I'm not sure what other supporting electronics are included.

Cheers