M3 EAP slowing down question.

[Hans217]

Does anyone out there have a issue with their EAP suddenly slowing down without anything within a quarter mile in front of me. several times now, I have had my car, in the wee hours of the morning commute, suddenly slow down almost braking. each time, this has been in a different area of my commute so I dont think that it is a GPS issue. is it possible that the car suddenly thinks that I am on side road?

 

[focher]

I have experienced this but in heavier traffic. I usually attribute it to a car next to me being too close to their lane edge, but I honestly don't know why it happens.

 

[Hans217]

I have experienced this but in heavier traffic. I usually attribute it to a car next to me being too close to their lane edge, but I honestly don't know why it happens.

I have had that too, especially when I am on a curve and passing the car in the lane next to me. but I have had it happen when that cars in front of me aren't close enough to register as ground me on my display.

 

[WileyTheMan]

I've seen a recurrence of this behavior since I got 2019.5.3. Rather, the car freaked out when a car merged into my lane (safe distance, not a cut). I felt bad for the person behind me.

 

[Hans217]

I've seen a recurrence of this behavior since I got 2019.5.3. Rather, the car freaked out when a car merged into my lane (safe distance, not a cut). I felt bad for the person behind me.

I had that happen to me in Portland as a vehicle changed lanes out from in front of me and the car sensed the Semi ahead of me going the same speed as I was.

 

[ewoodrick]

It happens, you'll see some references to shadows if you do a search

 

[Runebane]

I have found certain spots on my commute that the car on EAP will slow down on whether there is traffic or not. And it's usually certain lanes. it's very odd. I've learned to be in different lanes when I get close to those spots, but when I forget the car reminds me

I'm assuming it's either something reflective in that area that hits the camera/sensors just right, or something in the map meta data. Either way it's a tad annoying.

 

[Knightshade]

right lane approaching on ramps (expecting merging cars to come in) with Nav on AP I've seen it do this

 

[NYCR160]

The car see things we can not. Most appear to be real while some are obviously not. When mine slams on the brakes and after I respond by stomping on the gas I assume that the car just saw Elvis on the side of the road. Now, who would not slow down when seeing Elvis.

 

[NHK X]

Looks like you are from Tacoma. I live down in Olympia and get what you are describing. Not a hardware issue. Don’t think it’s a shadow issue here either along the i5 stretch but more likely due to changes in the road with construction. Would recommend not using AP while driving between 37th exit and until you pass the car dealerships up north. Think sometimes the car suddenly thinks your on a side street with all the changes.

 

[StellarRat]

I've had this happen twice in the same spot. I think it has something to do with the merge lane on the right even though both times there was no traffic in it. Maybe it thinks it's in the merge lane and not the right lane?? There is also a busy restaurant there with a parking lot that outlets into the highway, but no one was pulling out. It happened and I dealt with it, but I didn't have the wherewithal to try to get the speed zone the car had, look at other traffic, etc... hard to do all that when you're surprised and worried about getting rear ended.

 

[Jedi2155]

This happened to me FOUR times this past Saturday on a single trip between SD and Los Angeles (~220 miles). It happened at day,night, with cars, with no cars. So I haven't been able to pin down the exact cause. Really annoying and scary and makes me unable to trust Autopilot as of late. It happened starting with 50.6.

Its also not really location specific to me either since I've driven the same path (daily route home from work) and its fine some days but not on others.

 

[animorph]

Search for "phantom braking".

It can be a radar-caused reaction to stationary returns from an overpass or other nearby object. Radars are rather low resolution. Sometimes seems to be shadow-caused, which would be vision, but hard to tell since the shadow is probably caused by a nearby object. In any case, it's a trade-off between braking unnecessarily for phantom objects or not braking at all for real objects. Which would you prefer?

 

[gilscales]

The car see things we can not. Most appear to be real while some are obviously not. When mine slams on the brakes and after I respond by stomping on the gas I assume that the car just saw Elvis on the side of the road. Now, who would not slow down when seeing Elvis.

watch

 

[kbecks13]

As others have said, it can be the following items:

• Radar return from an overhead structure (i.e a bridge or road sign) <-- Most common in my experience
• Confusing road lines/shadows can sometimes confuse EAP and make it slow down, but i don't see this very often and normally am impressed that it can handle weird lighting situations without incident.
• Car in adjacent lane being at 10-11 o'clock or 1-2 o'clock relative to your car can cause EAP to slow down (it thinks the adjacent car may be in front of you)
• Being in a merging lane where traffic is entering can cause EAP to slow down and yield to other cars, but it slows down A LOT.
• Being on an interchange or relatively sharp (for a given speed) turn can cause EAP to reduce speed, however it will do this EVERY time it takes that route and not randomly.
• Being on an exit ramp (or what EAP thinks is an exit ramp), though it also would probably occur every time you take that route.

 

[dailo]

This has been especially bad in the most recent release. They are probably still fine tuning it, but with it was something you could turn on and off. Been having to turn off AP lately during my commute.

 

[kgroschi]

Does anyone out there have a issue with their EAP suddenly slowing down without anything within a quarter mile in front of me. several times now, I have had my car, in the wee hours of the morning commute, suddenly slow down almost braking. each time, this has been in a different area of my commute so I dont think that it is a GPS issue. is it possible that the car suddenly thinks that I am on side road?

Had a similar situation today. I was driving in the farthest to the left lane and the car wanted me to change into the carpool lane (navigate on autopilot) and my car suddenly braked pretty hard from 75 mph to about 55 mph because there wasn't a gap big enough to merge into the carpool lane. I ofc disabled the AP then and took over manually but the guy behind me wasn't happy, understandably. I also had some phantom braking maneuvers without anyone really ahead of me for 5 seconds or so.

That was in a friends M3 Performance with AP 2.5.

 

[NHK X]

Again in your case it’s likely due to construction given your location. Definitely not phantom braking. The times I’ve had it happen on this stretch of road I look down and the car thinks the speed limit is at non highway speeds. Might be after they rerouted the freeway left and right which is screwing with where it thinks you are based on its maps. Your right though, not always in the same exact location. Until they finish the construction I’m using TACC, don’t want to get rear ended.

 

[Nebuchadn3zzar]

I've experienced this in southern California, where HOV lanes have limited entry and exit zones. Having the "use HOV lanes" setting enabled causes Navigate on Autopilot to insist on using them, even if all other lanes are wide open and there's consequently no benefit in being in any particular lane.

As a result, if I'm driving in the leftmost lane adjacent to the HOV one, and I ignore the lane change suggestion that it invariably makes at each entry/exit zone, the car suddenly slows (without applying friction brakes) as it nears the end of the zone. I believe that is how Navigate on Autopilot signals to the driver that they are about to miss an exit. I find this sudden slowing unnecessary, thoroughly annoying, and potentially dangerous.

 

[WallyP]

As others have said, it can be the following items:

• Radar return from an overhead structure (i.e a bridge or road sign) <-- Most common in my experience
• Confusing road lines/shadows can sometimes confuse EAP and make it slow down, but i don't see this very often and normally am impressed that it can handle weird lighting situations without incident.
• Car in adjacent lane being at 10-11 o'clock or 1-2 o'clock relative to your car can cause EAP to slow down (it thinks the adjacent car may be in front of you)
• Being in a merging lane where traffic is entering can cause EAP to slow down and yield to other cars, but it slows down A LOT.
• Being on an interchange or relatively sharp (for a given speed) turn can cause EAP to reduce speed, however it will do this EVERY time it takes that route and not randomly.
• Being on an exit ramp (or what EAP thinks is an exit ramp), though it also would probably occur every time you take that route.

This "EAP Slow Down" happens to me on my daily commute on the I-5 in SoCal. This is different from "Phantom Braking," which I also experience on occasion. During some of the situations described above, the EAP max speed actually re-sets to a much lower speed on its own. In order to fix it I step on the pedal and then a message appears that "drivers assistance will not slow down" or something similar to that.

I'm on version 2019.20.4.2. Does anyone know if this a reported issue?