ACC: How is it supposed to work?

[atomic80]

I've had my X5 for a bit over a month now and wasn't really able to use the ACC during break in but now that I've finally broken her in, I'm finding myself wondering about its operation.

It seems slow to respond in traffic situations. For instance if there's a car in front of me, the X5 slows down (I have the follow distance set to minimum) but as soon as the lane clears up, it takes a bit of time before the ACC actually brings me back up to the preset speed. I've had to actually override a few times by pressing the accelerator. Also, when the car comes to a complete stop in rush hour traffic and starts moving, I can see the bars flashing but the X5 doesn't start moving. I had to again override by pressing the accelerator. If I hit the button presetting the speed then the ACC kicks in and the X5 starts moving again but not on its own. I was under the impression that the ACC would automatically start moving on its own from a complete stop.

[lovec1990]

first if you are stationary for some time ACC goes to sleep so you need too wake it by pressing resume button

[atomic80]

That's the thing, I wasn't stationary for very long. It was a stop and go situation. I probably shouldn't be using ACC in rush hour traffic anyhow. Was just wondering about it's operation as its meant to be designed.

[lovec1990]

atomic dont take this wrong way, but did you even bothered too read manuals?

[atomic80]

Originally Posted by lovec1990

atomic dont take this wrong way, but did you even bothered too read manuals?

I did and this is what it said:

"If the vehicle ahead of you brakes to a halt, the system is able to detect this within the given system limits. If the vehicle ahead of your drives away again from a halt, your vehicle is able to accelerate if operated accordingly."

That's the weird thing..mine doesn't start moving again. It just sits there until I either press one of the buttons or press the gas.

[sirajkas]

Mine is the same way. It detects vehicle a bit too late too especially when it is set at over 60mph..I almost have to step in and apply the brakes myself most of the time since the collision warning starts flashing too. Had I known it would be like this, I would have save the $1200. The option's name itself is misleading "acc stop and go"..

[USAusi]

I believe that if it is stopped for less then 3 seconds, it will take off again on its own, but if it is more than 3 seconds, then you have to tap the accelerator pedal for it to take off and get back up to speed.

[kip1]

Do the cars with Driving Assistant plus work the same way when the TJA is not activated?

Yes, it doesn't resume from stationary after 3 secs with or without TJA active. Very disappointing, you also have to press resume when you reach 25mph with TJA active, or it stays at 25mph even if traffic is moving faster again.

TJA is disappointing, but I like the responsiveness of the Acc, it's a lot better than previous versions. It can now detect stationary traffic and slow the car to a stop which is great but can be very irritating when it starts braking for parked cars!

[tleafs]

Agree, love this new feature but it will be even nicer if it can automatic resume after 3 seconds. Right now have to manually press resume.

[Socal2025]

I read somewhere that you may be able to code it to change the "sleep time" from 3 seconds to up to 10 seconds. This may help.

[USAusi]

Originally Posted by tleafs

Agree, love this new feature but it will be even nicer if it can automatic resume after 3 seconds. Right now have to manually press resume.

You can also just tap the accelerator pedal to make it go again.

[atomic80]

Originally Posted by Socal2025

I read somewhere that you may be able to code it to change the "sleep time" from 3 seconds to up to 10 seconds. This may help.

How about "0" time...I'll have to look into that!

Originally Posted by USAusi

You can also just tap the accelerator pedal to make it go again.

Thanks for that tip too! I noticed that too as well.