DRCC auto switch off

The message indicates the car also switched from Drive to Park. I have not heard of that before.

 

I guess they figure if too much time elapses without motion or interaction with the controls, it becomes more and more likely you're not fully in control of the vehicle, for one reason or another, so they play it safe.

 

@raspy ,. I've had the same thing happen on mine, but typically for me I reacted by stirring the selector, pushing pedals and buttons. By the time I'd realised what had happened, the message was gone before I could read it all.

 

No wonder you are confused

 

I try to be consistent. Maybe it's the only thing I'm inadvertently successful at.....

 

Even broken clocks are right, twice daily.

 

This is described on page 309 of the manual:

Automatic cancelation of vehicle-to-vehicle distance control mode Vehicle-to-vehicle distance control mode is automatically canceled in the following situations.
...
The following are detected when the vehicle has been stopped by system control:

• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.

It has to switch to Park - if the car reverted to Drive it would then release the brakes and creep forward into the car in front!

kevin

 

Good that it switched to park. Imagine if it just turned off and the car began moving forward. Actually you do have to monitor the DRCC all the time. Not often, but occasionally it will disconnect itself. I think it has an issue with following. There is a few beeps and a message.

 

One significant scenario where the DRCC will disconnect is if you are below 25mph and it loses sight of the vehicle it is following.

You cannot re-engage until you get up to about 30mph

Page 309 in the manual.

kevin

 

Thanks. Yes, I've had that happen and didn't understand what was wrong.

 

I find this a bit annoying but I suspect it was implemented that way to avoid the car accelerating to a high speed when you have been following slowly just because the car in front turns out of the line of traffic

One particular scenario that isn't handled very well is when you are following at a speed above 30mph, if the lead car turns into a left exit lane and the lane in front of you has stationery cars - quite often it will fail to see the stationery cars and accelerate towards them.

Usually I chicken out and apply the brakes, one time I left it until the AEB activated. I have seen this behavior in other vehicles with DRCC. I think the reason is that the radar system requires the target cars to be moving at least 1-2mph or it sees them as ground, and so not something to stop for.

The radars that are used for cars currently only have a single beam, they cannot distinguish up or down to tell if stationery object is a car, ground or maybe an overhead signal or sign except by its velocity.

The camera based systems (BMW i3 for example) have better imaging but they cannot get velocity from the doppler shift and they still suffered with the same problem (at least they did about 2 years ago).

kevin

 

I didn't look that up,but you maybe correct. I will test it at that 28MPG setting. That's all a bit strange, 28 because it will go to 0 and any speed in between.