Snow and Forward Collision Assistance System

[NLMGSAN]

This morning I was driving on the motorway in quite heavy snow. Al of a sudden this symbol of the
Forward Collision Assistance System Indicator popped up. This means one of the two supporting systems wasn't working. As the camera worked, it must have been the radar.
Did any of you ever experience the same ?

 

[Silver estate]

This morning I was driving on the motorway in quite heavy snow. Al of a sudden this symbol of the
Forward Collision Assistance System Indicator popped up. This means one of the two upporting systems wasn't working. As the camera worked, it must have been the radar.
Did any of you ever experience the same ?

Yep all time in trucks I drive , also heavy rain and spray does the same

 

[NLMGSAN]

Yep all time in trucks I drive , also heavy rain and spray does the same

Also with your Mg5?

 

[Coulomb]

As the camera worked, it must have been the radar.

How do you know that the camera was working? It's not the same camera as the forward 360° view uses.

My guess, despite having zero experience driving in snow, is that the camera near the rear view mirror was affected by the heavy snow. I assume that you would be using the windscreen wipers. Perhaps they are worn?

But I can also imagine that the radar would be confused by reflections from all the snow, adding noise to the signal.

 

[NLMGSAN]

How do you know that the camera was working? It's not the same camera as the forward 360° view uses.

My guess, despite having zero experience driving in snow, is that the camera near the rear view mirror was affected by the heavy snow. I assume that you would be using the windscreen wipers. Perhaps they are worn?

But I can also imagine that the radar would be confused by reflections from all the snow, adding noise to the signal.

Lane assist uses this camera. This worked without any issues. Also the display showed the vehicles in front of me. Camera worked.
Wipers are new. Car was serviced just before Christmas.

ACC uses the radar to determine the distance. This way the car reduces speed or it accelerates when cars are in front of you. But I almost ended up on the bumper of the car in front of me. Only then I realized ACC wasn't working, and then I spotted the indicator next to the lane assist graphics. No sound signal, no blinking to attract attention.
If snow can cover and disable the radar when ACC is on, the car must provide a clear audible warning because the car cannot behave as expected. In these condition I could have kissed that car in front of me easily if I would have braked (which I did of course) 5 miles further down the road. There, it was covered with snow and seriously slippery.

 

[ReintjeWA]

I thought the radar (also?) detects the vehicles in front? Because the camera can’t see through the car in front, yet the screen can see two cars in front of it. It was thought by some the radar looks underneath the car in front to detect this.

Although the other day I drove behind a car with a big trailer and that just showed up as one car. And this morning the car picked up on a ghost motorcyclist out in front that wasn’t there in my earthly realm. More guess-o-matic Inc. software?

 

[Coulomb]

It was thought by some the radar looks underneath the car in front to detect this.

I'm sceptical of that. The radar waves would go underneath the second car in front as well, unless there is some weird reflection off the road surface going on. It seems unlikely to me, but I suppose that it could work. But I don't see a whole lot of value to knowing the position of the car in front of the car in front.

More guess-o-matic Inc. software?

To be fair, getting this right for most situations is very difficult. That's one of the reasons that many believe that true self-driving is a long way off; you have to nail every corner case better than a human would.

I think that the intention of the current batch of driver assistances (excepting Tesla FSD, Waymo etc) is to "grab the low hanging fruit" of driver inattention, incapacitation (e.g. medical issue), and so on. Hopefully the regulators have done the analysis and decided that saving a few lives this way is worth the hassle for the many. Several on this forum have posted for example that automatic emergency braking has likely avoided an accident.

 

[NLMGSAN]

I thought the radar (also?) detects the vehicles in front? Because the camera can’t see through the car in front, yet the screen can see two cars in front of it. It was thought by some the radar looks underneath the car in front to detect this.

Although the other day I drove behind a car with a big trailer and that just showed up as one car. And this morning the car picked up on a ghost motorcyclist out in front that wasn’t there in my earthly realm. More guess-o-matic Inc. software?

It detects them as well but it adds metrics to the system the camera cannot provide.
To be honoust, I'm not sure how the second car in front is detected. Most of the time, if I recall correctly, I see them at a decent distance from the first. That could point at camera input, not radar. But next Monday I will pay some attention to it.

 

[okohll]

It detects them as well but it adds metrics to the system the camera cannot provide.
To be honoust, I'm not sure how the second car in front is detected. Most of the time, if I recall correctly, I see them at a decent distance from the first. That could point at camera input, not radar. But next Monday I will pay some attention to it.

Teslas do this mostly or purely with cameras, so I suspect it's the same.

The bottom line is theres no way I'd trust the MG ACC system in snow given the patchy way all the driver assistants work at the best of times, I think for everyone's safety it would be best to disable them and concentrate.

 

[JonnyG]

I've had this quite often in the past with VW Golfs and their ACC / front collision assist etc. They used to only have radar so I always had to keep the front sensor area clean in Winter and expect any snow/sleet to block it with resultant warnings. It used to be a square under the front reg. then was in the front badge on VW Golfs.

I'm guessing the MG4's is behind the front bumber to the side of the reg. ? ( based on previous posts on here about it's position) ... and not the square in the lower front grill area.

 

[NLMGSAN]

Teslas do this mostly or purely with cameras, so I suspect it's the same.

The bottom line is theres no way I'd trust the MG ACC system in snow given the patchy way all the driver assistants work at the best of times, I think for everyone's safety it would be best to disable them and concentrate.

Tesla left the path of the radar to make systems cheaper. While they claimed it was better, first versions were clearly not....
MG uses radar and camera. It is described in the manual.

 

[Silver estate]

I've had this quite often in the past with VW Golfs and their ACC / front collision assist etc. They used to only have radar so I always had to keep the front sensor area clean in Winter and expect any snow/sleet to block it with resultant warnings. It used to be a square under the front reg. then was in the front badge on VW Golfs.

I'm guessing the MG4's is behind the front bumber to the side of the reg. ? ( based on previous posts on here about it's position) ... and not the square in the lower front grill area.

Re your VW ACC , Then the same would stand for a MAN truck as they’re part of the same group

 

[okohll]

Tesla left the path of the radar to make systems cheaper. While they claimed it was better, first versions were clearly not....
MG uses radar and camera. It is described in the manual.

Sorry, I meant seeing the car in front of the car in front.

But in general, however it works, I'd be turning off collision assist, lane keeping and ACC when snowing. Unexpected steering jerks or braking could be very dangerous.

 

[NLMGSAN]

Sorry, I meant seeing the car in front of the car in front.

But in general, however it works, I'd be turning off collision assist, lane keeping and ACC when snowing. Unexpected steering jerks or braking could be very dangerous.

I get it.
I think your advice is ok although personally I would never mess around deep down the menus to disable LKA or AEB. It's the snow that is as dangerous as the failing system itself.