[bpeckham]

Maybe one of you Z owners out there can answer this question. According to the owner manual, the radar-guided cruise control can brake if it approaches a slower vehicle ahead. Do you know if the cruise control will also brake when descending a hill?

There's a hill near my house where the speed limit is 50. If I coast down the hill, I'll be doing 70 at the bottom. The cruise control in my wife's Audi will brake on descent to keep the set speed. I just wonder if the Z will do the same, or is it just when approaching a slower car?

 

[Maggie’s Dad]

I would try it for you, but, we don’t have any hills in Florida!

 

[bpeckham]

I would try it for you, but, we don’t have any hills in Florida!

Appreciate the thought!

 

[deibu]

Yes. The adaptive cruise control keeps you right at the set speed even on very long steep [7% 6miles] declines. However it is extremely annoying that it also slows you down going around corners. If I try to go around a corner at 75, iut will invariably slow me down to 72 or worse...very annoying! Once you get used to it, you just disengage the cruise control on corners...

 

[bpeckham]

Yes. The adaptive cruise control keeps you right at the set speed even on very long steep [7% 6miles] declines. However it is extremely annoying that it also slows you down going around corners. If I try to go around a corner at 75, iut will invariably slow me down to 72 or worse...very annoying! Once you get used to it, you just disengage the cruise control on corners...

Thanks @deibu. What if you're using the old-school, not-radar-guided cruise? Does it still slow down on descent?

 

[deibu]

Great question. Didn't know I could turn the adaptive cruise off. But here it is. I will give it a try and get back to you!

5-45 HOW TO SELECT THE CRUISE CONTROL
MODE
Selecting the vehicle-to-vehicle
distance control mode
To choose the vehicle-to-vehicle distance
control mode , quickly push and release
the MAIN switch .
Selecting the conventional (fixed
speed) cruise control mode
To choose the conventional (fixed speed)
cruise control mode , push and hold the
MAIN switch for longer than approximately
1.5 seconds. See “Conventional
(fixed speed) cruise control mode” (P.5-
59).

5-59
CONVENTIONAL (fixed speed)
CRUISE CONTROL MODE
This mode allows driving at a speed
between 25 to 90 MPH (40 to 144 km/h)
without keeping your foot on the accelerator
pedal.
WARNING
. In the conventional (fixed speed)
cruise control mode, a warning
chime does not sound to warn
you if you are too close to the
vehicle ahead, as neither the presence
of the vehicle ahead nor
the vehicle-to-vehicle distance is
detected.
. Pay special attention to the distance
between your vehicle and
the vehicle ahead of you or a
collision could occur.
. Always confirm the setting in the
ICC system display.
. Do not use the conventional
(fixed speed) cruise control mode
when driving under the following
conditions:
— when it is not possible to keep
the vehicle at a set speed
— in heavy traffic or in traffic
that varies in speed
— on winding or hilly roads
— on slippery roads (rain, snow,
ice, etc.)
— in very windy areas
. Doing so could cause a loss of
vehicle control and result in an
accident.

 

[deibu]

Great question. Didn't know I could turn the adaptive cruise off. But here it is. I will give it a try and get back to you!

5-45 HOW TO SELECT THE CRUISE CONTROL
MODE
Selecting the vehicle-to-vehicle
distance control mode
To choose the vehicle-to-vehicle distance
control mode , quickly push and release
the MAIN switch .
Selecting the conventional (fixed
speed) cruise control mode
To choose the conventional (fixed speed)
cruise control mode , push and hold the
MAIN switch for longer than approximately
1.5 seconds. See “Conventional
(fixed speed) cruise control mode” (P.5-
59).

5-59
CONVENTIONAL (fixed speed)
CRUISE CONTROL MODE
This mode allows driving at a speed
between 25 to 90 MPH (40 to 144 km/h)
without keeping your foot on the accelerator
pedal.
WARNING
. In the conventional (fixed speed)
cruise control mode, a warning
chime does not sound to warn
you if you are too close to the
vehicle ahead, as neither the presence
of the vehicle ahead nor
the vehicle-to-vehicle distance is
detected.
. Pay special attention to the distance
between your vehicle and
the vehicle ahead of you or a
collision could occur.
. Always confirm the setting in the
ICC system display.
. Do not use the conventional
(fixed speed) cruise control mode
when driving under the following
conditions:
— when it is not possible to keep
the vehicle at a set speed
— in heavy traffic or in traffic
that varies in speed
— on winding or hilly roads
— on slippery roads (rain, snow,
ice, etc.)
— in very windy areas
. Doing so could cause a loss of
vehicle control and result in an
accident.

If you follow the above instructions to turn off the adaptive cruice control, and use the CONVENTIONAL CRUISE CONTROL, then it holds the set speed through corners, going up hilss, and then also on the downhill descent. That is to says , yes, it utilizes some breaking to maintain the set speed going downhill...

 

[bpeckham]

Thanks, @deibu. Good to hear. It sounds like the more fun mode since it doesn't slow down around corners, yet still prevents you from getting a speeding ticket on a long descent (not that it's ever happened to me 😉. Okay, it has.)

 

[MindScape]

Yes. The adaptive cruise control keeps you right at the set speed even on very long steep [7% 6miles] declines. However it is extremely annoying that it also slows you down going around corners. If I try to go around a corner at 75, iut will invariably slow me down to 72 or worse...very annoying! Once you get used to it, you just disengage the cruise control on corners...

To be fair, I actually like that it's slowing down a bit on corners - I was worried the first time I was using it on a highway change that it would accelerate too hard on the corner, but then it slowed down a bit and kept a nice pace through it that was smooth.