nyjohnchan

I have an o6 with tech package. The CMBS never give any warning while I'm driving. I tried to come very close to the car in front of me, still nothing. I have to brake before I really rear end somebody. How do you know if the system is working? I did not manually turn it off. According to the manual, the system starts working when speed is over 10 mph @ 300 ft or closer.

sotiri

Try this:
Go on to the freeway during a quiet time, set the cruise control to 85.
Now override the system just by depressing the accelerator slightly, even though you are lightly pressing on it, the car will actually slow down.
Now that you have established control over the system and yet the ACC is on and set, speed up behind a car on the freeway and close the distance to less than one car length by accelerating quickly- then just take your foot off the gas pedal.
the system should see that you are close enough to activate BRAKE BRAKE, and actually brake the car to the distance you selected on the ACC.

nyjohnchan

I thought the CMBS works independently without the ACC being on. Or both systems have to be at the same time?

VOdoc

It seems the CMBS does not kick in below 25-30 mph as it has only gone off (BRAKE BRAKE) at higher speeds for me. It does seem to be more vigilant when ACC is active.

Kind of a disappointment, as stop-and-go traffic is where most fender-benders occur. Would be nice if Acura could reprogram it for more utility at lower speeds.

sotiri

it does work independently, but with the ACC on and on the freeway, you will have enough time and error protection to test the system.
The CMBS will factor in the rate of closure based on relative speed, and IF the CMBS isnt working and the ACC is, the system will just brake the car, without activating the warning system.
CMBS starts to work at over 10mph. There is a way through the service to select the CMBS to work more actively.
I have had the CMBS frequently activate when I do what I suggested. In fact I use that procedure to demonstrate it without driving on regular streets.
the freeway is a great place to do that because the likelyhood of a sudden stop occuring at 65mph on a light traffic conditions is remote.
the system is fooled when you approach a car from behind at a speed greater than 10mph than the rate of speed of the traffic.
But when you have the ACC on, and you jackrabbit behind a car on the freeway, the CMBS overrides the ACC. So if the CMBS isnt functioning at least the ACC will track the traffic and applhy the brakes to maintain distance.
Be sure to set the ACC distance to the closest setting.

lland

I've never figured out a good way to safely test the sytem since to do so you have to get pretty close to the car ahead without touching the brakes. Mine has activated three times, each when the car in front of me decided to make a sudden right turn. The first two times I just got the beeps and "BRAKE" warning message. The third time I got the tug on the shoulder belt. Pretty cool and it does get your attention.

In contrast. the active cruise control is relatively easy to test.

LL

lumpulus

Personally, I think this ACC is a disaster waiting to happen, but then I don't trust cruise control anyway.

sotiri

the best test I ever had was without trying.
I was driving on Peterson (in Chicago) by Ashland when the car in the left lane decided he wanted to make a right turn into the gas station.
before I could even get my foot to the brake, the system was already in full braking, and I mean it was full force with the beeps, when I did put my foot on the brake I remembered that the pedal was firm and when I took control of the system, the warning ceased-but I was able to bring the car to a full stop in less than 2 seconds. I would dare say that the system gave me a 2 second braking head start over me moving my foot off the gas and on the brake and apply maximum pressure.

nyjohnchan

It's good to hear that the system does work.

CL6

It is if you set it to the shortest distance and turn your brain off. But, set to the longest distance, it is very nice to use.

And if you want to test the CMBS just follow a friend on the freeway and get them to drive at a steady 65 mph and hope they don't stop suddenly!

petemc

I trust that you are suggesting that this be done with a friend in another car ... rapidly accelerating to within 1 car length on the freeway, with someone who hasn't got a clue what you are doing, is a good way to rapidly make enemies with other drivers

Pete

sotiri

Chicago drivers, we are used to it. LOL

anacuraloyalist

A lot of these posts talk about getting really close to the vehicle in front of your RL, but does everyone understand that CMBS only uses the closing rate to detect a possible collision? That means that you could slowly get closer and closer to the vehicle ahead, and actually make contact without CMBS activating. That's because you would have a lot of time to correct that mistake, and maybe you're doing it on purpose, though I can't imagine why. What CMBS does is alert you when you are suddenly approaching a vehicle or object at a very high closing rate, meaning that your RL is traveling much faster than the vehicle in front of you and a crash is quitely likely to occur.

black label

The only way I have been able to test is is being very brave on an off ramp with a car in front of me. I have demonstrated it for customers in this fashion at the beginning of a test drive in this fashion. I have only been able to get to stage 2 of CMBS once.

anacuraloyalist is right though, tailgating alone won't set it off, it relies on closing speed between you and the object.

Acura demonstrated it with a truck that had a bar stickin off to the passenger side that had a metal plate on it. They had the truck driving and had the RL drive at a faster speed towards the plate hanging down not at the back of the truck.

dwboston

Why is the CMBS so much more active with the ACC on than with the ACC off? With ACC set on the highway I get flashing BRAKE warnings much more frequently when a car slows down in front or cuts in front of me than in the same situations with the ACC off. Explain that.

TampaRLX-SH

Maybe when you turn on ACC you have told CMBS that you ave surrendered the driving to the driving to the car. Perhaps the logic to alert more frequently is akin to 'HEY BOZO! ARE YOU PAYING ATTENTION!? GET OFF THE TEXT MESSAGING AND LOOK AT THE BUS YOU ARE ABOUT TO SLAM INTO! I CAN ONLY DO SO MUCH HERE!"

With ACC off, it figures 'OK, maybe BOZO will pay a little more attention and has SOME control.'

Just a theory.

(yes it was a joke...forgive me BOZO fans).

SpicyMikey

I tested mine using UHaul Moving boxes faced with alluminum foil. I crashed into the boxes at 30mph. it proved that my car did not react to a stage 1 until 2-3 seconds before impact, no stage 2 occured, and the stage 3 triggered at a fraction of a second before impact with moderate braking. Is howed the video to Acura Client Services and they confirmed the system was acting as designed.

IMO, the system is almost useless. It certainly doesn't work as described in the sales literature. I file a Demand Letter with Acura on September 15th. If they don't respond within 30 days (this week) there will be legal action initiated. If anyone wants to know more or is interested in joining the suit, please PM me.

black label

I've never tested it on a fixed object, only by charging towards the back of another moving vehicle on an off ramp. I think my boss would be pretty upset if I made a habit of crashing cars into boxes covered with aluminum foil.

I am very intersted in the outcome of your suit. You may have a hard time with it. My guess is they can say if it slows the car at all than it works as designed. Remember its CMBS not CABS, "M" for "mitigation" not "A" for "aversion". It was never intended to avoid an accident on its own, it was only intended to reduce the forces of impact.

You should definitely start a thread once (if) you get some response from Acura.

SpicyMikey

There's been plenty of threads and discussions here and elsewhere. Do a search if you're interested. Seems discussion is over for now. After viewing my video, Acura's position is that it works as designed. That's fine. We believe them now. Problem is that's not what the advertising suggests and describes. That's the real argument. Since Acura never responded to the legal Demand Letter, we'll just need to let the courts decide if Honda misled us.

Can't say much more now. However, I will certainly be happy to provide updates as they occur. Some others on this board are involved as well but I am leading the efforts.

TampaRLX-SH

Mikey, perhaps that box test was not convincing enough for Acura?

May I suggest: Get the Acura rep who insists it is working correctly to stand in the road (a closed test track, of course), wrapped in tinfoil. If he is convinced it is working properly, you can just aim the RL and stomp the throttle. I am sure he will be steadfast in Acura's assertion CMBS works per spec.

And while you are at it, you can validate the hood hinge mechanism designed to lessen the impact to pedestrains.

That oughtta convince them, one way or another.

SpicyMikey

LOL, I didn't try that suggestion

Although, considering the fact that no Acura rep would EVEN take a test drive with me, gives me the feeling they already know the system doesn't work as advertised.

dwboston

I agree with Mikey - it's pretty clear the system doesn't work as advertised. There was an RL ad that specifically focused on the CMBS with the car driving in fog approaching a slower moving vehicle ahead. In that ad, the car gives audible warnings well in advance of anything seen in real world driving. The really oversold the capabilities in that ad.

SpicyMikey

Unfortunately, those ads and commercials are what sold me on the feature. I'm not happy about that athough I love everything else about the RL. Regardless, I could have taken a pass on this CMBS feature and saved $4000!!

Chas2

I cannot remember where, maybe TOV, that the spring loaded hood hinge is not a USDM feature. I have to search for where I found this.

dwboston

It's on the European Legend. It's called a "pyrotechnic pop-up bonnet". The upper part of the hood pops up if the car detects a pedestrian impact to keep the person from hitting their head on the windshield.

Chas2

pyrotechnic? More explosives in the car than just the airbags now!

TampaRLX-SH

This one? Next to last post...indicates it does have this feature.

http://www.vtec.net/forums/one-messa...sage_id=707865

And here...

http://www.carpages.ca/go/roadtest/2...road_test.aspx

And not so definatively here...

http://corporate.honda.com/press/article.aspx?id=4199

And here....

http://www.theicct.org/documents/German_Honda_2006.pdf


It appears not so much a spring loaded feature, but the hinge brackets allow absorbson of the pedestrians body by the hood structure to reduce head injury and buffer the body from the engine block & windshield.

Chas2

This is the European feature I am talking about that is not included in the USDM RL. Unlcear to me whether it is included in the JDM....second article from Consumer Reports would indicate not, which is surprising.

Improved pedestrian safety
A pop-up hood further enhances pedestrian safety. On collision, three touch sensors in the front bumper detect the danger and activate a pyrotechnic actuator. In a fraction of a second, the rear edge of the hood lifts by 100mm. This provides ample clearance between the hood and the hard engine components beneath it. If the head or shoulder of a pedestrian hits the relatively soft hood, this will buckle. The pop-up hood can therefore significantly reduce the risk of serious injury.

http://www.worldcarfans.com/2060704.004/3

*************
Next up, says Honda, are pop-up hood systems, such as the one Honda developed for its Legend sold in Europe, According to Honda: “This is a system that senses when a pedestrian is struck by the bumper and then uses a pyrotechnic charge (similar to an airbag inflator) to lift the back edge of the hood about 3 to 4 inches.”

http://blogs.consumerreports.org/saf...rian_safe.html

*************
This is an interesting article that speaks to costs...Pedestrian safety appears to be much more of a European issue, and is not even on the radar screen, it seems in the US.


So how are auto manufacturers meeting these requirements? Well, currently, there are two main design concepts. In order to prevent fatal head-strikes on the hood, automakers are forced to create some crush space between the hood and the engine block. There are basically two ways the safety community has been looking into this: 1) active hoods and 2) passive hoods. The active hood would actually deploy the hood away from the engine in the event of a pedestrian impact, allowing for more flexibility in vehicle styling and a sleeker hood line. It is currently installed in the European Honda Legend, the Citroen C6, and the Jaguar XK. I have heard estimates from a reliable source that active hood systems add about $500 to the price of a new car, which is substantially more expensive than similar pyrotechnic safety devices such as airbag modules (around $20). This is mostly due to difficulties with the deployment sensors (detecting pedestrian impacts is much more difficult than detecting a frontal crash), the fact that these systems need to survive while being exposed to the elements, and of course the lack of market penetration for this new technology.

Mostly because of the cost and complexity with the active hood system, the passive hood is what nearly all European cars are currently going with in their current designs. The passive system, simply put, permanently designs a dead-zone between the hood and the internals of the engine compartment. Of course, this is the culprit for the high hood line of the MINI's new front en

http://www.motoringfile.com/2006/11/...tion-analysis/


*************
This has nothing to do with the pop up system but has to do with the aluminum hood....


Development of Aluminum Hood for the 2005 Model year LEGEND
Accession number;04A0774390
Title;Development of Aluminum Hood for the 2005 Model year LEGEND
Author;HAYASHI NOBORU(Honda R & D. Co., Ltd., Tochigi Labs.) ANDO KATSUTOSHI(Honda R & D. Co., Ltd., Tochigi Labs.) KASHIWAGI MASAKAZU(Honda R & D. Co., Ltd., Tochigi Labs.)
Journal Title;Honda R&D Tech Rev

Journal Code:L0353A

ISSN:0915-3918

VOL.16;NO.2;PAGE.17-22(2004)
Figure&Table&Reference;FIG.12, TBL.2
Pub. Country;Japan
Language;Japanese
Abstract;An aluminum hood was developed for the 2005 model year LEGEND in order to reduce costs while maintaining durability and performance requirements and help ensure pedestrian safety. We focused on materials cost reduction for the aluminum hood skin sheet by reviewing its chemical composition and developing a 5000 series alloy produced with the continuous casting directed rolling method for the stiffener sheet. Planning for general purpose processing specifications, a PVC-free acrylic acid resin system mastic sealer for steel and aluminum was applied for adhesion between the various components. Continuous multipoint self-piercing rivets were applied for the reduction of machining costs. The surface was treated with a surface conditioner that has a zinc phosphoric crystal as its main component. This allowed the precise formation of a chemical conversion coating on the surface. The frame structure of this developed hood was also optimized, enabling it to achieve the same performance in pedestrian safety as a conventional steel hood. (author abst.)

http://sciencelinks.jp/j-east/articl...04A0774390.php

TampaRLX-SH

Pyrotechic? Holy crap!

That would likely launch the flailing pedestrian off the LEGEND in back into the road for an oncoming bus to finish off!

I think the energy absorbtion of the ACE design is a wiser, more passive approach. But also, the latest front end design of new car models have been more upright and blunt. This is part of the pedestrian impact requirements being adopted in many global markets.

If I am not mistaken, Europe currently has the strongest mandate for this pedestrian safety technology and perhaps the pyro bonnet of the LEGEND was the market specific resolution?

black label

I don't care what it does, I just want to be able to say my car has a pyrotechnic bonnet.

SpicyMikey

It just seems like the incident is going to end badly for the pedestrian no matter what you do. Crumple zones? Raised hood to avoid contact with the windshield? Is that going to really matter in a highspeed impact.

anacuraloyalist

Well, actually, CMBS is not more active in that condition, ACC is telling you to brake. It's on page 250 of the owners manual for my '06 RL. Both CMBS and ACC use the BRAKE warning, but they have different meanings. What you are saying is better sensitivity of CMBS when ACC is on is really not CMBS at all, it's ACC telling you that you are tailgating someone and need to slow down right away.

dwboston

No kidding - I'm aware that ACC uses the BRAKE warning. The question is why are there not the same warnings in exactly the same situations with the ACC off? Is it not important to "slow down right away" when ACC is disengaged? The CMBS TV commercial shows audible warnings (presumably accompanied by BRAKE warnings) several seconds in advance when approaching a slow moving vehicle from behind at high speed (in limited visibility in the case of the commercial even though the manual states it may not work in fog) - in the real world you don't get such warnings until within a car length or so.

Since you want to quote the manual, it also states that ACC will not bring the car to a complete stop (page 241), yet it does. Is the manual always 100% accurate?

anacuraloyalist

I'm really not trying to pick a fight with you, but does ACC seriously bring your car to a stop? Mine definitely does not, I can feel it suddenly release the brakes when it slows to 25 MPH. The first time it really scared me because I expected it to stop the car, but when it released the brakes it actually felt like the car was accelerating, even though I know it wasn't.

Yeah, I've found other mistakes in the owner's manual too, but let's not attack each other personally, I thought this was a forum not a championship ultimate fighting ring.

dwboston

Yes - it has brought my car to a complete stop.

No comment on the other point in my previous post about CMBS not functioning as advertised?

anacuraloyalist

Sure, my comment is that CMBS does pretty much exactly what I expected it to do. Please don't be insulted, but I really don't understand what the big flap is all about. My expectation was that it would work as described in the brochure and by the saleseman at my dealer. I understand that it is based on the closing rate between my RL and the vehicle in front of me, and that it will respond differently in traffic than it will against a fixed object. This is new techonlogy, and just like when seatbelts were first required, there is a lot of confusing information and reactions will vary from person to person. But I am proud to be on the cutting edge of the future of safety by having CMBS on my RL. I show it off to my friends, and they are amazed by it. My friend with a Benz S550 is blown away that the CMBS in my RL that cost half us much as his car works so much better than his, although his will actually bring his car to a complete stop. CMBS has saved my bacon more than I'd like to admit in traffic around Los Angeles, and for that I am very thankful. It has also raised my awareness about how inattentive I can be when I'm driving, which has been extremely humbling for me, but its the truth. I can think of two times when I would definitely have rear-ended the car in front of me, albeit at fairly low speeds, but thanks to CMBS there isn't a scratch on my car, or a mark on my insurance. How's that for a comment?

Chas2

Let me understand this. So you have to be running in ACC, get into a "Brake Brake" situation, as in someone cutting in front of you, and the ACC will slow the car to a stop?

Is it a firm hard brake, or just the sort of gentle brake, when it is adjusting speed at say 60 mph?

Currently, I have only had the situation where the ACC was on following a car, but then the speed dipped below 25 and it cut off (Got to watch those small, one horse, southern towns!), or when it advises to brake, and I really agree, and brake, then the system cuts off.

dwboston

I have had it set driving around town (on 40 mph roads), and had a car slow down in front of me to take a left turn. I got brake warnings and the car slowed itself down (I could have intervened at any time but let the car do it itself). The ACC did not cut out at 25 mph and the car slowed all the way to a stop.

Chas2

Thanks! I never would have tried that. Still don't know if I will if the opportunity presents itself, but it is good to know the car can do that!

SpicyMikey

My experience is different with the ACC. I've found that if the ACC is turned on the system will perform it's normal light braking and continually slow the car down until it reaches 20mph (maybe it's 25, I can't remember). Anyway, at that point I get an audible alarm as the ACC shuts off and the braking disengages.