JLB
Posts: 4
Joined: Sun Jul 13, 2014 2:49 pm

Cruise control.

Mon Jul 14, 2014 8:24 pm

Hi, I currently drive a BMW 335i and enjoy using the cruise control as it is maintains a constant speed while driving uphill and or downhill. This is convenient; I do not need to break to maintain a specific speed. My question for current i3 users, does the i3 cruise control function the same way? Is there any fluctuation when CC is engaged? Thanks.

i3Alan
Posts: 304
Joined: Wed Jul 09, 2014 4:08 pm

Re: Cruise control.

Tue Jul 15, 2014 8:50 am

JLB wrote:Hi, I currently drive a BMW 335i and enjoy using the cruise control as it is maintains a constant speed while driving uphill and or downhill. This is convenient; I do not need to break to maintain a specific speed. My question for current i3 users, does the i3 cruise control function the same way? Is there any fluctuation when CC is engaged? Thanks.
I am still waiting for my i3 to get assigned a boat to bring it to me (hopefully today!), but I'll take a stab at answering. The BMW spec does clearly imply that regen is used if needed during cruise to keep speed correct even when going down hill. My guess is that your 335i will accelerate above your set speed on a steep enough downhill where engine compression cannot provide enough braking will above your set speed.

On the other hand, if you only use your cruise above 85 MPH where engine braking combined with wind resistance can handle any hill steepness, they you are probably correct. :D

BrianStanier
Posts: 255
Joined: Sat Oct 19, 2013 12:00 pm
Location: Durham, UK

Re: Cruise control.

Tue Jul 15, 2014 9:32 am

The i3 does maintain the set cruise speed up and down hills although I don't use it as I dislike the feeling of not being in control. Instead I use the soft speed limiting available in eco pro mode. However you can only have one speed limit (in my case 65mph).

jadnashuanh
Posts: 5196
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Cruise control.

Tue Jul 15, 2014 11:33 am

On my GT while on cruise, if the hill is steep enough, it will downshift to keep the speed in check if letting off on the accelerator isn't enough. The first time it did that came as a surprise as no previous vehicle did that. The i3 seems a little slow to recognize it's going back up a hill before it then tries to maintain the speed, but I think some of that is to avoid large spikes in power. Hilly roads may not be the best for the use of the cruise control, but if you have a lot of speed enforcement around, it can be useful to your wallet!
Jim DeBruycker
2014 i3 BEV, 2021 X5 45e
(The i3 will be sold soon, <17K-miles, interested?)

Stevei3
Posts: 365
Joined: Mon Sep 02, 2013 9:02 am
Location: the Netherlands

Re: Cruise control.

Tue Jul 15, 2014 11:52 am

i3Alan wrote:My guess is that your 335i will accelerate above your set speed on a steep enough downhill where engine compression cannot provide enough braking will above your set speed
Hi guys,

not entirely correct, for it depends on the type of CC you have in your current BMW. Most models have 'Cruise Control with Braking Function' since recent years. As for the i3, check for the option '544 Cruise Control with Braking Function' in the spec list . My guess is 544 is fitted as standard on most markets (like the UK) but not in others (upprice 'Comfort' package here in NL).
Cruise Control with Braking Function will actualy apply the brakes when the car cannot maintain speed otherwise (downshift, regen etc.), hence the name :)

Regards, Steven

stumbledotcom
Posts: 453
Joined: Sat Jan 18, 2014 3:35 pm
Location: San Francisco
Contact: Website

Re: Cruise control.

Tue Jul 15, 2014 6:58 pm

jadnashuanh wrote:The i3 seems a little slow to recognize it's going back up a hill before it then tries to maintain the speed, but I think some of that is to avoid large spikes in power.
The few times I've used cruise control I've noticed that it spends a lot of time in coast mode. And my efficiency rating shown in the i.app goes through the roof. Last freeway trip hit 85%. For comparison, I get 20% or less during my normal commute on city streets.

Agree with Stevei3's comments on cruise control with braking function. It's standard in the US. Have it on my '09 E90. Keeps your speed pegged on what's set even going down significant hills. My i3 has the tech package which includes Active Cruise Control. I haven't used it enough on open roads to gauge how it reacts to hills. In traffic, ACC will bring the vehicle to a complete stop and has no problem accelerating with the pace of the vehicle in front.

JLB
Posts: 4
Joined: Sun Jul 13, 2014 2:49 pm

Re: Cruise control.

Thu Jul 17, 2014 5:36 am

Thanks guys. My 335i keeps speed constant irregardless of uphill, downhill. This is a nice feature and I have grown accustomed to the function.

amateurish
Posts: 102
Joined: Mon Dec 16, 2013 9:10 am
Location: MK, UK

Re: Cruise control.

Thu Jul 17, 2014 6:04 am

I use cruise control a lot and can confirm that it does maintain speed even when going down steep hills where it will use heavy regen if necessary.

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