Has anyone noticed a difference in ACC function since this update?

I notice that the onset of braking when in ACC is more gradual, less abrupt. I assume this is from the change in CMBS programming, since CMBS is an integral part of ACC. Acceleration after a slowdown is also less abrupt.

Or is this just placebo? In any case, makes it easier for me to keep the system activated in rush hour traffic.

 

Now that you mention it, I have been worrying whether I've been imagining things.

To me, it looks like following distances have changed a little bit, too. To get the same following distance that I used to get with 2X hash marks, it seems to me that I would now need 2.5X hash marks.

LOL.... Umm...yeah, I think they overdid it a little bit with that one. :-) Now it seems to me that it's prudent to help it along because people behind me aren't going to wait for ACC without getting on the bumper or moving like they're wondering if they should pass.

Not a big deal. If that's what I need to do, I can do that.

No, I don't think you're imagining things or experiencing a placebo effect.

I'm on the verge, though, of wondering why I let them do it. There's a chance that I prefer the old programming.

One thing that's annoying is the car's reaction to all the lane barrels in construction zones. The old system ignored them.

The new programming, in exactly the same places under exactly the same circumstances, will flash the orange light against the windscreen and flutter the accelerator pedal to warn me that it thinks something's amiss.

When you think about it, it's very nice that the car can do odd things like flutter the pedal against your foot to get you to pay attention. But in my case, when it's doing it is unnecessary.

Better safe than sorry, I suppose.

 

I'm glad it's not my imagination, then.

I drive through two construction zones on the way downtown, complete with orange barrels. I can't say I've noticed that. I'll test it when I can.

 

So I drove through two construction zones with yellow barrels close to the road today. No errant triggering of CMBS.

I will confirm my observations that the CMBS programming changes have smoothed out driving in heavy traffic with ACC on. Two examples:

1) As I noted a few posts above, the onset of braking and acceleration are more gradual/MUCH smoother. Before, the acceleration was abrupt to the point that I had to lower the speed limit on ACC when entering heavy traffic. It was as if the car wanted to go back from 25 to 72 mph in a hurry, when the traffic ahead was only going 33 mph and about to stop again. Now, the acceleration is not as hurried and is faster to slow down if traffic ahead slows--that is, reacting before where it would have before.

2) When a car cut in front of me suddenly, I didn't get the flashing "BRAKE" in the MID, but the braking did begin milliseconds later, and again in a way that was more progressive and smooth than before. Before, it would have been almost jamming on the brakes.

So, overall, the CMBS reprogramming seems to have helped ACC?

Anyone else? Bueller?

 

Thanks for your observations. I will schedule my first service (A 1) in the next few weeks and will have two TSBs done - the CMBS and Homelink.

If the CMBS evens out the ACC stuff it will save me from comments and dirty looks from my wife. The abrupt movements drive her crazy. I'll post how it works for me.

 

I have not been generally using ACC because I have felt that the car can't drive as smoothly as I can. But based on your comments, I turned it on for this morning's 150 mile ride from MA to ME. I left it on the whole time - 100 miles highway with light to moderate traffic and 50 miles two lane road with moderate to heavy traffic. I believe that the ACC system is now noticeably smoother - with less abrupt changes in speed and acceleration/deceleration. Even in stop and go traffic, the car seemed more steady, accelerating perhaps even less than I might do myself. Though it's possible that I never gave it a full chance before and that my perception is colored by the discussion, I really do think the system was improved and made smoother by the CMBS update.

 

In the past two weeks I've driven 2900 miles. Here are my observations:
1. The ACC will take itself off in heavy rain. It will soldier on for a while, show signs of getting unhappy and then give up. Heavy rain in this case is a summer thunderstorm dropping mass quantities of rain.
2. The ACC in its most minimal distance setting had an average of one car every five minutes insert themselves in the gap. You quickly get attuned to putting your foot on the accelerator and applying some throttle so as to keep the ACC from jumping on the brakes. It flashes its warning but complies with the driver's intent (you) to stay off the brakes.
3. 90% of Interstate driving I kept the ACC on. The other 10% the traffic was too aggressive and/or dense to let it do its job while keeping to the brisk pace I was driving. If I were content to hunker down in the right lane and run with the slowest traffic, it would have likely been fine.
4. I'd like to see the ACC judge vehicle speed faster. Example: a faster car pulls in front, but does not leave much space. The ACC wants to apply brakes. However, if a faster moving car is far ahead and moves into my lane, the ACC slows and then resumes speed. If it were quicker at judging the speed differential, most of this frustration would be eliminated.
5. All in all, ACC makes long trips less tiring and is a great option to have.

 

Where it happens with me is Jeff Davis Hwy (Route 1) where improvements are being made between Quantico and Occoquan.

They're trying their best not to disturb historic properties and at the same time accommodate new developers and their shopping centre and condo.

The net result is that it's very curvy, and the barrels can be quite close to the car. To be honest, if I were parking, I believe the parking sensors would go off...they're that close.

But it wasn't happening with the old firmware.