Phantom braking at night with 2022.44.11

[srs5694]

I've had 2022.44.11 for three days now, and for the first time since receiving it, I did a 45-minute drive after dark. (It actually began at late dusk, and by the end it was completely dark.) This drive was mostly on the highway, and phantom braking was awful. I experienced it probably about a dozen times (I'm not exaggerating). What's more, three times (early in the drive, so before all daylight had gone), it wasn't just phantom braking; the car actually reduced my set driving speed. I was driving in a 65 mph zone, and the first time, it reduced my set speed to 45 mph and began to brake to achieve that speed. I used the thumb wheel on the steering wheel to set the speed back up. A minute or so later, it decided that even 45 mph was too fast in this 65 mph zone, and reduced my set speed to 35 mph. I disengaged Autopilot, waited a minute or two, and re-engaged it. Two or three minutes later, it reduced the set speed to 55 mph, which I bumped back up again. There was nothing obvious to prompt such speed changes -- no changes in the speed limit (and in fact the speed limit display on the Tesla's screen stayed at 65 mph), no traffic jams, no emergency vehicles, etc. The remaining incidents were more typical phantom braking events -- the set speed limit didn't change, but the car decided to start braking for no apparent reason.

This trip was a return home from work, where I'd stayed later than usual today. I did not experience anything similar on the trip in, which was during daylight hours; or on a trip to or from work on Tuesday, when it was daylight or at least much lighter during my evening commute. (Wednesday I worked from home.) I'd say that either I was very unlucky in the phantom braking lottery this evening or this build of the software is particularly prone to phantom braking at dusk or at night. I'm mainly posting this as a warning to others to be cautious with this build, since this is a potentially dangerous regression.

 

[ELETRO]

mine almost got rear ended smh

 

[clydeiii]

I've had 2022.44.11 for three days now, and for the first time since receiving it, I did a 45-minute drive after dark. (It actually began at late dusk, and by the end it was completely dark.) This drive was mostly on the highway, and phantom braking was awful. I experienced it probably about a dozen times (I'm not exaggerating). What's more, three times (early in the drive, so before all daylight had gone), it wasn't just phantom braking; the car actually reduced my set driving speed. I was driving in a 65 mph zone, and the first time, it reduced my set speed to 45 mph and began to brake to achieve that speed. I used the thumb wheel on the steering wheel to set the speed back up. A minute or so later, it decided that even 45 mph was too fast in this 65 mph zone, and reduced my set speed to 35 mph. I disengaged Autopilot, waited a minute or two, and re-engaged it. Two or three minutes later, it reduced the set speed to 55 mph, which I bumped back up again. There was nothing obvious to prompt such speed changes -- no changes in the speed limit (and in fact the speed limit display on the Tesla's screen stayed at 65 mph), no traffic jams, no emergency vehicles, etc. The remaining incidents were more typical phantom braking events -- the set speed limit didn't change, but the car decided to start braking for no apparent reason.

This trip was a return home from work, where I'd stayed later than usual today. I did not experience anything similar on the trip in, which was during daylight hours; or on a trip to or from work on Tuesday, when it was daylight or at least much lighter during my evening commute. (Wednesday I worked from home.) I'd say that either I was very unlucky in the phantom braking lottery this evening or this build of the software is particularly prone to phantom braking at dusk or at night. I'm mainly posting this as a warning to others to be cautious with this build, since this is a potentially dangerous regression.

Was the GPS unit confused about which road you were on? Perhaps it thought you were on the frontage (access) road next to the highway..?

I saw similar behavior to what you described but only when the GPS was confused.

 

[srs5694]

Was the GPS unit confused about which road you were on? Perhaps it thought you were on the frontage (access) road next to the highway..?

I saw similar behavior to what you described but only when the GPS was confused.

I can't say I studied the map very carefully; however, I can say that the speed limit icon in the display did not change. I'd expect it would have changed had the car's GPS mis-recorded the position as being on a parallel surface street. (Unless maybe it changed for a brief period and then changed back, in which case I might not have noticed.)

 

[derotam]

I can't say I studied the map very carefully; however, I can say that the speed limit icon in the display did not change. I'd expect it would have changed had the car's GPS mis-recorded the position as being on a parallel surface street. (Unless maybe it changed for a brief period and then changed back, in which case I might not have noticed.)

Can you provide the specific location where this happened? Maybe someone else there can test at that location as well.

 

[Dewg]

This is common for Tesla vehicles, and I wouldn't classify it as phantom braking. The car is telling you exactly why it's braking by showing you the reduced set speed. Phantom braking is when the car slows down for no apparent reason - here we have a reason.

As to why the car reduced the set speed, there are a few possible reasons, the most common being that the car decided that the set speed was too fast for its safety profile. This typically happens on curves, where the car will slow down on freeway on/offramps even though the speed limit is faster. Since you indicated that the drive was at night, the car may have had reduced visibility for the cameras and decided to slow down to ensure a safe reaction time. You also indicated that the daylight version of the trip did not experience this, which could further point to the system losing visibility/confidence in the low light.

My recommendation is to make sure the car and cameras are clean, calibrated properly, and there is sufficient light (either high-beams, street lamps, other cars). There are also times where the system needs to reboot. Some people find that if they disable Sentry Mode at home or at the office every so often, the car can go into a deep sleep and reset the system on wake up.

Hopefully this helps with future drives.

 

[srs5694]

Can you provide the specific location where this happened? Maybe someone else there can test at that location as well.

I-95 South from Needham, then following I-95 when it split with I-93.

This is common for Tesla vehicles, and I wouldn't classify it as phantom braking. The car is telling you exactly why it's braking by showing you the reduced set speed. Phantom braking is when the car slows down for no apparent reason - here we have a reason.

I related the three instances when the car changed the set speed, because I don't recall it ever happening to me before; I've had my car for four years. Even if it's happened to me once or twice before and I've forgotten, the frequency of that issue on Thursday's commute home was WAY out of proportion to my own experience with my car. Whether you call it "phantom braking" or not is a semantic quibble; the symptoms are almost identical, and equally dangerous in either case.

In addition to those three instances, there were multiple other instances of more "traditional" phantom braking, bringing the total instances (including those three) to something on the order of 12. (I didn't count, so I could be off either way by two or three.) I've definitely experienced "conventional" phantom braking before, especially after getting my first FSD-enabled build back in late 2021; however, I've never experienced it as frequently as I did last night.

This is well outside the realm of normal for my car and in my experience, which as I say, covers four years of ownership. What I experienced was not common.

Some people find that if they disable Sentry Mode at home or at the office every so often, the car can go into a deep sleep and reset the system on wake up.

I rarely use Sentry Mode, and I did not use it Thursday. Checking TeslaFi, my car was asleep for a solid 8.5 hours before my drive home.

As I said, I suspect that the problem is a new one in the latest software build and has to do with the late twilight conditions. I've driven that route before many times, including in similar conditions, and the car has never done that before last night.

 

[Dewg]

I-95 South from Needham, then following I-95 when it split with I-93.

I related the three instances when the car changed the set speed, because I don't recall it ever happening to me before; I've had my car for four years. Even if it's happened to me once or twice before and I've forgotten, the frequency of that issue on Thursday's commute home was WAY out of proportion to my own experience with my car. Whether you call it "phantom braking" or not is a semantic quibble; the symptoms are almost identical, and equally dangerous in either case.

In addition to those three instances, there were multiple other instances of more "traditional" phantom braking, bringing the total instances (including those three) to something on the order of 12. (I didn't count, so I could be off either way by two or three.) I've definitely experienced "conventional" phantom braking before, especially after getting my first FSD-enabled build back in late 2021; however, I've never experienced it as frequently as I did last night.

This is well outside the realm of normal for my car and in my experience, which as I say, covers four years of ownership. What I experienced was not common.

I rarely use Sentry Mode, and I did not use it Thursday. Checking TeslaFi, my car was asleep for a solid 8.5 hours before my drive home.

As I said, I suspect that the problem is a new one in the latest software build and has to do with the late twilight conditions. I've driven that route before many times, including in similar conditions, and the car has never done that before last night.

Let us know if any of the other suggestions help improve performance.

 

[TexasDuke]

Still experiencing phantom braking with OTA 2022.45.15 in 17MS 75D while only using cruise control.

 

[jfabula]

When ever I get phantom braking, I take over right away specially on busy highway. We as driver are still responsible. Good luck