Undocumented Cruise Control Surprise

[Mad Mac]

In every vehicle I've owned since 1968
that had cruise control
one simply holds down the set+ button
until the desired speed is achieved
then release the button.
Which is what the 500 page owners manual
for my 2021 Rubicon JT says.

What a surprise when I lifted off the button
and it kept accelerating
until tapping the break at 90 mph.

By trial and error I determined
one click on the set+
increases speed by one mph
as described in the owners manual.

However, holding down the button
a full second or so
increased the speed to a multiple of 5 mph.
In other words three or four full seconds
would increase speed from sixtyish to 75.
And it always stops on a multiple of five.

There is no mention in the owners manual
of the 5 mph increment feature
(or is it a hazard)
that scared the hell out of me.

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[Shopshirt]

I use that feature all the time makes it seem a little more accurate to me. Didn't realize that was not in the manual I just happened to notice that is how it works.

 

[ATL_Rubi]

I learned this the hard way too, my old VW used to go +/- 5 mph per hit, and it took a second of holding to adjust it by +/- 1 mph. Jump in the jeep the first time, hold the button for a few seconds thinking I can go from 63-67ish, jumps up to 80 real quick.

 

[sharpsicle]

That's a beautiful poem!

I think that's a great feature to have. Different from your cars in '68? Sure. But I don't see it as a problem. And these days, different manufacturers are going to have slightly different programming. Some will even be opposite of this.

 

[Y-Guy]

How long to you have to press it to go into plaid?

 

[steveorama]

My wife's Subaru jumps +/-5mph every time you press the cruise up or down and you have to hold it to increase or decrease in multiples of 1mph. I personally hate it, as usually I just want to bump up or down my cruise speed a mph or so based on traffic flow around me.

By contrast the JT cruise operates just like my last couple of vehicles where it only bumps up or down by 1mph as needed. I don't think I've ever found the need to hold the cruise down to make large speed adjustments. If it's more than 5 mph than I just speed up or slow down and once I reach the speed I want to cruise at, I just reset the cruise setting. So I don't think I even knew the cruise control on these would do that since I only press it once or twice at a time and never hold it down.

 

[Jwarrenod]

Works the same way in my wife’s S5 Cab and in every other Audi and Dodge we’ve had too.

JW

In every vehicle I've owned since 1968
that had cruise control
one simply holds down the set+ button
until the desired speed is achieved
then release the button.
Which is what the 500 page owners manual
for my 2021 Rubicon JT says.

What a surprise when I lifted off the button
and it kept accelerating
until tapping the break at 90 mph.

By trial and error I determined
one click on the set+
increases speed by one mph
as described in the owners manual.

However, holding down the button
a full second or so
increased the speed to a multiple of 5 mph.
In other words three or four full seconds
would increase speed from sixtyish to 75.
And it always stops on a multiple of five.

There is no mention in the owners manual
of the 5 mph increment feature
(or is it a hazard)
that scared the hell out of me.

 

[Rokon]

Actually, if you look on page 329 of your users manual it documents the 5mph increment if set button is held down.

 

[Lunentucker]

This is the exact opposite of our Subaru. The default quick single press on that is up or down to the next increment of 5 mph. A longer press moves in 1 mph increments.
So let's say I'm cruising along a four lane at 62, and I hit a new zone that's posted higher. A single press will move me to 65, but if I want to go 67 I'll have to hold it for a few seconds.

I like the next five as default on Subie. It works great for those who like to run any zone at +5.

 

[GrubbyBaja]

Thanks for the info...I had no idea the cruise would jump by 5 if the + button was held. I usually just bump it +or- 1 or 2 at a time. I don't really see an issue with the +5, +10, etc. but I also don't have to worry with rapid acceleration on the highway since I have to manually downshift if I want acceleration (6-speed MT). Probably a bit different with the auto tranny.

 

[ShadowsPapa]

In every vehicle I've owned since 1968
that had cruise control
one simply holds down the set+ button
until the desired speed is achieved
then release the button.

Not sure what you've driven - but I can't recall mine working like that. I always pushed the gas until I reached the speed I wanted, then hit set. I might get it close and then push the button one at a time, or hold for the 5s until I got to where I wanted.
I've known about the 5mph thing with Jeep for a long time. I think my wife told me regarding one of her Grand Cherokees.

Page 174 in my PDF version -

 

[Labswine]

Never used that feature. I simply accelerate to the new desired speed and hit the set button again. Always did that in any vehicle I had with cruise control.

 

[ShadowsPapa]

Never used that feature. I simply accelerate to the new desired speed and hit the set button again. Always did that in any vehicle I had with cruise control.

I've driven hundreds of miles with my feet in a comfy position, using only the cruise buttons to handle speed changes. When I go through a small town after driving 70 I hit the set - button to drop to 55 or even 45, then set + after I get past that town and the local cops. Never touching the pedals.
Even nicer with the 4xe as in max regen, you only need the brakes at the very last to come to a full stop. max regen in combination with the cruise - nice, easy driving. Can drive for hours without foot fatigue.

 

[Panthers65]

Never used that feature. I simply accelerate to the new desired speed and hit the set button again. Always did that in any vehicle I had with cruise control.

X2, not sure when I would need to run my cruise up that much. Turn CC on, get to my speed, hit the set button. if the speed limit drops by 5, i just hit the "-" 5 times. Increases by 5 just push the "+" 5 times. Don't use my cruse control on 2-lane roads, only long highways and interstates.

 

[Mad Mac]

Actually, if you look on page 329 of your users manual it documents the 5mph increment if set button is held down.

For my 2021 Rubicon, page 329 is about SSC
(Selec Speed Control) if equipped
which I do not think I have
and does not mention the 5 mph increment.

When I was driving today, I noticed
that the small digital speed display
below the clock shows the "aspirational" speed.
So if a person does not want to count
one-one-thousand, two-one-thousand
they can watch that instrument.

Personally, I prefer to count
and not take my eyes off the road.

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