Understanding the AP1 Autopilot Penalty Box

[mr_hyde]

Hello! I purchased a new-to-me 2014 MS P85D from the original owner at the end of February and I love the car with one annoying exception - The Autopilot. It frequently disengages and doesn't respond to any commands. I have paid special attention to what is happening when it shuts down and there doesn't seem to be any pattern. Sometimes I can do 50 miles on the interstate and sometimes it shuts off after a minute or two. Sometimes it won't even engage after the car has been parked for hours.

I'm not debating the 'nags' or basic limitations. I'm simply trying to understand if I'm doing something wrong or if my car is malfunctioning. I have actively kept my hands on the wheel with gentle inputs while watching the road, etc. with the intention of not going into the penalty box.

It would be less annoying if I could still use TACC when the steering function shuts off, but that is disabled too. Are there any good threads that talk about this? I have found a few, but none I have found seem to match my experience. Thanks for any help you can provide!

 

[fasteddie7]

What happens when it “shuts down”? For AP1 there are a very specific set of conditions that need to be met to make it available to engage. If it shuts down due to the system being unable to safely continue you get a red hands and steering wheel in the binnacle display with a loud alarm like beeping. If it shuts down due to what it perceived as inattentiveness, there are several white flashes which speed up and get more intense until you get the red hands and will be unable to re-engage autopilot until the car is stopped and put in park.

 

[mr_hyde]

When it shuts down/off, there is a single chime and that is it. Suddenly I’m steering and the car is coasting to a stop if I don’t touch the accelerator. If it try to re-engage the TACC (single pull on the stalk) or the Autopilot (double pull on the stalk), nothing happens. Sometime, when I try to engage either system early in a drive, neither system will engage. I’ve tried different combinations of behaviors and can’t find a pattern. These include perfect behavior of two hands on the wheel and continual gentle steering inputs, hands off the wheel and everything in between. Extended hands off seems to shut the system down the same way the good behavior does; just in a predictable way.

 

[fasteddie7]

If it’s a chime and not a “buzzer” that is manual disengagement. If the wheel is torqued too hard or brake is pressed you’ll get a chime and the wheel icon with flash from blue to grey a few times. If you aren’t inadvertently disengaging it there may be an actual hardware problem. Autopilot disengage due to lack of attentiveness or a challenging road condition it cannot navigate is hard to miss since it lets off several high pitched warning beeps. If it’s a chime, as you say, that’s user disengagement, or what the system perceived as user disengagement. Also when you pull the stalk twice to re-engage autopilot and it doesn’t work, it’s always accompanied by 3 buzzer like beeps and a message in the binnacle that it is unable to engage at this time.

 

[mr_hyde]

Interesting. I've seen the message that it is unable to engage occasionally but that is usually if I try to launch when the lines are the road are in poor condition or occasionally in poor weather conditions. When it won't engage the other times, it simply does nothing - like the stalk isn't attached to anything. The car does seem to pull to one side slightly. All cars tramline differently on different surfaces so I don't know if this is normal or not, but I'm going to take the car to an alignment shop and see if there there is a mechanical issue next.

 

[mr_hyde]

Update on this. It occurred to me that the car had seemed to be pulling slightly to the left which I couldn't always contribute to the crown in the road. I also had a bubble in the sidewall of a front tire that prompted me to replace the front tires and get an alignment which I did today. The shop made some adjustments to the FR caster and the rear toe which would have contributed to the car pulling. On the 20 minute drive home, the autopilot didn't disengage once.

My working theory is the alignment was causing the car to pull which caused the steering input from the autopilot to be near, but not past, whatever its tolerance is. This caused the system to say 'NO!' at frequent, though unpredictable, intervals depending on the crown in the road I was driving. With the alignment back within specs, the steering inputs will be more gentle and the AP will be happy to run normally.

I hope I'm correct. I'll report back if there are issues. I have a 70 mile drive in the morning - all freeway and I intend to sit there and listen to a new audiobook while AP1 does the hard work!

 

[mr_hyde]

The function is still intermittent. At the start of a drive today, the TACC and AP wouldn’t engage at all. On the way home, both worked fine but shut off 15 minutes into the drive even though I had my hands on the wheel the whole time and didn’t see a single warning. Does the system generate any logs Tesla could use to see why it is shutting off? There was a two tone chime when it shut off so it seems to be actively disengaging.

 

[fasteddie7]

Two tone chime where it's a high tone followed by a low tone is autosteer disengaging (high tone) followed by TACC (low tone) this is either a brake pedal or stalk movement as if it were steering wheel torque it would only disengage autosteer, not TACC. It should be making three buzzer type beeps to communicate autopilot is unable to engage. The only two things that can happen are the three buzzers or autopilot engages. If there are times that neither one happens, perhaps the stalk is malfunctioning or there's bad wiring on there causing the issue. My guess would be the stalk and/or the wiring is failing.

 

[Zuikkis]

It must be either the brake pedal sensor or the stalk itself.

For some reason car thinks you are manually turning TACC off.

Broken or uncalibrated steering wheel sensor would only disable autosteer, not TACC.

 

[mr_hyde]

This is helpful, thanks. A faulty switch or stalk would explain why it won’t work at all sometimes at the beginning of a drive. I think next time it is working, I’ll just leave my hands off the wheel and induce a true penalty box scenario and pay attention to how it acts. If the problem is the brake switch, shouldn’t the brake lights be on in the little vehicle graphic?

 

[Zuikkis]

Yeah, brake switch should activate the brake lights too. So very likely it is the stalk.

If you ignore autopilot nags, first it will try to wake you with very loud beeps and red steering wheel flashing in the display. If you let that happen a few times (three maybe?) it will disable autosteer completely for that trip. However TACC will continue to function even after that. So that can't be what you are experiencing.

 

[mr_hyde]

Okay, a couple updates. Zuikkis is absolutely on the right track. Today I purposefully ignored the AP warning and it shutting down was nothing like I have been experiencing. The title of this thread is all wrong. On the 2nd leg of my drive, I got my usual failure. Once it fails, the TACC speed target shows the speed but I can’t adjust it with the stalk and the steering wheel icon is visible when I’m not applying steering inputs and goes away briefly when I do provide inputs. The stalk is completely unresponsive up/down/front/back but I can adjust the following distance by twisting.

As an added data point, if I brush the brake with my left foot, the brake lights come on and the system immediately scolds me for pressing both pedals at once. How many years have I practiced to commit THREE pedals at once to muscle memory and now I don’t even have time to drive that car! I digress….

Is this a likely contact failure inside the stalk? Is this a DIY project? Have these failed regularly? Thanks a million for all of your help.

 

[mr_hyde]

Hello again. I wanted to close the loop on this issue in case someone has something similar happen and finds this on a search. The SC identified that my camera was crashing and basically disabling the AP and TACC system until the next driving session. They said it was the original camera and was a 3rd party manufacturer without firmware control. They claim they installed the newest (mono) camera made in-house. It was about $700 including the diagnostic but the system does work now. What they said about older versions of the camera made me nervous about trying to buy one on eBay and DIY. Normally I would DIY something like this. I hope the info helps someone.

 

[mr_hyde]

Well... the loop isn't closed yet. The issues continued after the SC replaced the Mobileye camera. Because I was clear with them when I approved the work (and got it in writing), that I expected a $700 credit towards more work if their diagnosis didn't fix the problem, I went back to the SC for more troubleshooting. They couldn't find an issue but I was able to have a discussion with their senior tech. He confided that the logs are not very good on the early cars and that they only captured one of the dozen plus instances for which I sent time stamps of the failure. We looked at that log together and found that the stalk is commanding the forward-press 'cancel' command at the same time I experience the failure and holding it there for the duration of the drive.

This is pretty much what Fasteddie7 and Zuikkis suggested earlier in this thread. The tech and I agreed we would wait to confirm one or two more times with the logs and then replace the stalk. I'll report back here when there is some conclusion.