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Hi Folks, I live in a rural area of the mountains. Does anyone know if ACC will brake for you going downhill without a car in front of you? That would make it worth it more than traffic jams. My commute is 22 miles over the mountain and through the woods. It is 30 minutes door to door to my work with no stoplights. I am more interested in how ACC would do generally at lower speeds on gently curved roads.

Second question is related to how I was a little disappointed when I saw the front end of a ACC Volt. It looks kinda cheap and wished they had murdered it out in black instead of imitating chrome. So I would consider getting it dipped or painted black, yet wonder if that will interfere with what ACC needs to operate properly? Has anyone researched this yet? I am not finding much info on the net and would assume it would be OK if one avoids any metallic paints.

Thanks
Jon
 

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Does anyone know if ACC will brake for you going downhill without a car in front of you?
Jon, I don't know the answer to your question, but when I'm in the Rockies I throw the car in Low. Then when the cruise lifts off the throttle, Low keep speed in check even in very steep downhills.
 

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The cruise control won't let you go any faster than what it is set for, also putting the car in low is a great idea as it will save the brake pads.

There may be some parts of the road (sharp turns, etc) where you will want to go slower than the speed set by cruise control. If there are no cars ahead of you it won't know to slow down so you would still need to override it with the brake pedal.

My dad has a Subaru Legacy with ACC and I drive with it engaged going down a mountain road. Usually there is another car ahead that it will lock on to and follow so when the car ahead brakes, our car brakes. But if there is no car ahead it will try to go to whatever I have the speed set to, which in some cases is too fast. The car doesn't know what the road ahead is like, whether it is straight or curved, uphill or downhill, etc.
 

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Usually there is another car ahead that it will lock on to and follow so when the car ahead brakes, our car brakes.
It seems like it might be a bit sketchy to use ACC in those conditions because if there's a sharp enough curve the car ahead might move so far to one side that the ACC looses "lock" on it and then your car would suddenly accelerate to the pre-set cruise speed just as it goes into said sharp turn.
 

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With the cruise control on, and the car in LOW, the Volt will use regenerative braking to keep the speed right at the set speed at all times, so you should never have to use the brake pedal except for curves.
 

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Hi Folks, I live in a rural area of the mountains. Does anyone know if ACC will brake for you going downhill without a car in front of you? That would make it worth it more than traffic jams. My commute is 22 miles over the mountain and through the woods. It is 30 minutes door to door to my work with no stoplights. I am more interested in how ACC would do generally at lower speeds on gently curved roads.

Second question is related to how I was a little disappointed when I saw the front end of a ACC Volt. It looks kinda cheap and wished they had murdered it out in black instead of imitating chrome. So I would consider getting it dipped or painted black, yet wonder if that will interfere with what ACC needs to operate properly? Has anyone researched this yet? I am not finding much info on the net and would assume it would be OK if one avoids any metallic paints.

Thanks
Jon
That sounds like one of the last conditions I would use cruise control to be honest.
 

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Adaptive Cruise Control acts like standard cruise when there is nothing to 'adapt'. If the downhill is a steep decline, regen may not be enough to prevent overspeed. No cruise I know of will apply brakes unless there is a vehicle in front.
 

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Adaptive Cruise Control acts like standard cruise when there is nothing to 'adapt'. If the downhill is a steep decline, regen may not be enough to prevent overspeed. No cruise I know of will apply brakes unless there is a vehicle in front.
Adaptive cruise has braking capability, so I don't see why it shouldn't be able to apply the brakes.

But if it doesn't then it's computer control of the accelerator pedal. So, it can use as much regen as lifting off allows. That means it can do more when the car is in Low.
 

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I live in the Denver area and have used ACC in the mountains with my 2017 Volt. It does maintain the speed you set downhill, with regen to maintain the speed. It works perfectly, no need for L mode. I do recommend using mountain mode, as it really helps keep the engine from working too hard on the inclines. The power to pass with this car is so much fun!


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Adding: I used ACC up and down a curved road to Echo Lake. When I hit a curve that was too sharp, it was really nice to hit the regen paddle to slow down quickly for the curve. I could then resume ACC with the same hand. It made the drive quite fun.


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I have not found any need to put the transmission in low for ACC to use regen as a means to limit speed. Car does it just fine in drive. I just love the ACC system on the Volt. You do have to be careful, as mentioned, when using it on a twisty road. It's not impossible for it to lose the car ahead and start accelerating.
 

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Adaptive Cruise Control acts like standard cruise when there is nothing to 'adapt'. If the downhill is a steep decline, regen may not be enough to prevent overspeed. No cruise I know of will apply brakes unless there is a vehicle in front.
Personally, with a Gen 1 Volt and simple standard cruise control driving in Low, I have never seen a condition where regen is not enough to present overspeed.

The only time I can imagine this is possible is on steep grades below 25mph, but cruise can't be engaged under 25mph anyway, and most cruising is at highway speeds.
 

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Personally, with a Gen 1 Volt and simple standard cruise control driving in Low, I have never seen a condition where regen is not enough to present overspeed.

The only time I can imagine this is possible is on steep grades below 25mph, but cruise can't be engaged under 25mph anyway, and most cruising is at highway speeds.
On my road trip last September, I used CC and L in the Rockies and in California, where sharp curves abound. My trick, which worked in more than 99% of the time, was to flick the speed selector toggle of the CC. Driving in L would allow rapid decrease in speed with that technique, and then acceleration, again through toggling the lever, to the posted speed limit. I hardly ever needed to apply the foot brake. Those road conditions required paying close attention and I don't think that the lack of brake lights illuminating bothered the following drivers that much, at least I never heard honking horns or observed getting the bird.:cool: Most curves could be taken at 25 mph even though they would be posted at 20 mph. Those posted at 15 mph or lower needed me to slow below 25 mph with the foot brake. I own a 2014.
 

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I doubt braking would be a problem but the curves might be. The car makes no effort to slow down on a curve, so your speed might be too high going into sharp curves. Now rural roads in Iowa would be fine. West Virginia would be an issue (from what I remember).
 

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Just to reiterate what's been said a few times already:

I have a Gen I Volt, and the car will automatically *slow* (using regen) to the cruise control speed if you're driving in Low. I've done this many times, and will notice the power gauge showing regen when going down slopes on cruise control. This is just plain cruise control, so I assume ACC would behave the same way if there's no car in front.
 

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Adaptive cruise has braking capability, so I don't see why it shouldn't be able to apply the brakes.

But if it doesn't then it's computer control of the accelerator pedal. So, it can use as much regen as lifting off allows. That means it can do more when the car is in Low.
ACC will not apply the brakes unless it 'sees' a slower car ahead.
 

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It seems like it might be a bit sketchy to use ACC in those conditions because if there's a sharp enough curve the car ahead might move so far to one side that the ACC looses "lock" on it and then your car would suddenly accelerate to the pre-set cruise speed just as it goes into said sharp turn.
That's why I say ACC doesn't relieve the driver of driving the car. In my Mercedes, I turn down the ACC set speed for the current conditions, exactly for that reason.
When coming down the long straights on I-70, it's set for 70. When you get to the twisties near Golden, it's turned down to 60 or 55.
If you're going into a sharp turn, you should be on the brakes, which disengages cruise anyway.

It's not autopilot, it's a cruise control. Don't over think it, and don't let it drive the car.
 

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I have not found any need to put the transmission in low for ACC to use regen as a means to limit speed. Car does it just fine in drive.
In most places, no. Come out to Colorado, there are Interstates where "D" has insufficient regen braking to keep the car from running downhill over the set speed, and mountain roads are much steeper than Interstates. "Low" is most definitely required.
 

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Quick question:

Is the front collision detection always on or is it only on when using ACC? Just considering whether to get the option on our 2017 Volt.

Mike
 

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Quick question:

Is the front collision detection always on or is it only on when using ACC? Just considering whether to get the option on our 2017 Volt.

Mike
Always. Though collision detector in the confidence 2 package is slightly different than the one in ACC.
 
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