new Model S - misbehaving ultrasonic proximity sensor?

[f-stop]

I took delivery of a new 70D yesterday, awesome car. But all day today I started getting false warnings from one of the front left ultrasonic sensors when there was absolutely nothing near the front left bumper.

As long as the car was in Drive but the car at or near a full stop with foot on the brake, the proximity warning would chime and visual warning on the dash would light up repeatedly, until I started driving forward again.
For example, I took this photo while backed into a parking space in an otherwise empty parking lot, car in drive but foot on brake, looking out to a view of a beach. Nothing anywhere near front of the car.

or I could be stopped at a traffic light, as the first car in line with no cars to the left or right of me and a clear intersection ahead, and I'd get this warning. Or I could be several feet behind a single car directly in front at a stop, yet the left proximity warning would chime/light up. If I get closer to the car in front, I'd see the normal forward proximity warnings light up as expected, in addition to this left corner warning.

There's no dirt or debris on the bumper where the sensors are located. I'm puzzled why this didn't happen yesterday as it only started today. I'm wondering if the sensor there is way out of alignment (could it out of alignment and aimed at the ground??). Or is there some kind of calibration that goes on automatically with the sensors? the only other possible factor is that I park in a very very tight garage (though the left front bumper corner is no closer to the wall than the right front)

I guess I will call service tomorrow if the problem persists, but meanwhile wondering if anybody has seen this before? Any suggestions before I call? thx

 

[vitaliy]

Haven't read your post yet, but it looks like Tesla is sacrificing quality to get numbers. Bad idea.

 

[rcarpen22]

Pdxgibby had the exact same problem on a brand new car a few days ago:
Model S Technical / Mechanical Issues - Page 266

 

[Max*]

There is a TSB for too much paint on the parking sensors, call the SvC, it's a quick swap if they have your color in stock, otherwise they need to order parts.

I had the same thing when I got my car, it didn't start right away though.

 

[pdxgibby]

Hey f-stop. Congrats on the car. Thanks, rcarpen22 for the cross-post. Yes, I had the same problem. Another interesting tid-bit / symptom that I noticed is that if you turn the wheel to the right while you are getting the false alert, the 1st parking sensor should start giving false alerts as well. Some sort of algorithm where it assumes that if there was an alert at one sensor and you turn away from it, the next sensor will trigger even if that sensor is not bad. Funny that this is the exact same sensor that I had a problem with.

My Service Center ordered me a new sensor, but it hasn't come in yet. There were other issues with my front bumper (dents caused during manufacturing) just below and to the left of the 5th sensor (counting from the driver door around the front) and another dent below and to the right of the 2nd sensor. They ended up swapping my bumper + 6 new sensors with another midnight silver metallic showroom car owned by Tesla that had just arrived. So I got the sensors and bumper from that new car and it got mine. The paint color looked virtually identical, but I haven't seen it in the sunlight yet. We all hope this fixes both the sensor issue and the dents.

There are also dents in the rear bumper -- but those are less noticable.

We checked other vehicles with similar VINs and they all had this dent to some degree, though some are less pronounced.

I will be picking up my car sometime today and hopefully all of my initial delivery issues will be resolved. Fingers crossed.

 

[Jaff]

I have had this happen, but only when the sensor was blocked by snow / ice / salt.

I was actually surprised that it only took a relatively thin layer of "road salt" to defeat the sensor.

 

[JeffS]

I get this same sensor misbehaving after every car wash. I wash the car every other day or so at a place with a really nice touchless high pressure system.
After every wash, I use a Ryobi 18V battery leaf blower to dry the nose, the rear, the wheels/rims, outside mirrors...and now...I make sure I put the air flow on that sensor for 10 or 15secs to get any water that is in there, out. Solved the problem for me.

I don't get much road grime build up on my car because I wash it so often. But it's a thing...that sensor...it's finicky. Car wash. Something to remember.

-Jeff

 

[f-stop]

Hey f-stop. Congrats on the car. Thanks, rcarpen22 for the cross-post. Yes, I had the same problem. Another interesting tid-bit / symptom that I noticed is that if you turn the wheel to the right while you are getting the false alert, the 1st parking sensor should start giving false alerts as well. Some sort of algorithm where it assumes that if there was an alert at one sensor and you turn away from it, the next sensor will trigger even if that sensor is not bad. Funny that this is the exact same sensor that I had a problem with.

My Service Center ordered me a new sensor, but it hasn't come in yet. There were other issues with my front bumper (dents caused during manufacturing) just below and to the left of the 5th sensor (counting from the driver door around the front) and another dent below and to the right of the 2nd sensor. They ended up swapping my bumper + 6 new sensors with another midnight silver metallic showroom car owned by Tesla that had just arrived. So I got the sensors and bumper from that new car and it got mine. The paint color looked virtually identical, but I haven't seen it in the sunlight yet. We all hope this fixes both the sensor issue and the dents.
[...]

thanks pdxgibby & others, sorry I didn't come across your post in the other thread. yes it sounds like the same thing. interesting your observation about turning the steering wheel slightly. I haven't (yet) noticed any other little problems after delivery, but I'll call the SC to have this checked out. It was a bit rainy yesterday, so I wonder if JeffS' observation about the problem after washing the car means a problem with water getting into the sensor?

update: for some reason today the problem seems to have gone away. About 5 minutes after leaving home today (it was sunny at the time), it happened exactly once. But then never again at all today, even later in the afternoon rain. Strange. I guess I'll just have to wait to see if it happens again.

 

[f-stop]

update - just to conclude this thread for reference, the problem persisted intermittently after my original report. as noted previously the problem seemed worse on rainy days. but it was annoying enough even on perfectly dry days that I simply turned off the parking sensor chimes for the past couple months.

the Service Center confirmed this is a known problem - for some reason a batch of cars including mine were built with too much paint on some of the parking assist sensors. I finally had two of the front left sensors replaced today under warranty (it took a while for the parts to arrive and to get an opening for a service appointment). They actually measured the paint thickness on all the sensors, and just replaced the two that were out of spec. I see on the work order that the good sensors all measured paint thickness of 130-140µm. The two bad sensors had paint that measured 155µm and 160µm and so were replaced. Just FYI in case anybody else is seeing this problem.

 

[tmoz]

update - just to conclude this thread for reference, the problem persisted intermittently after my original report. as noted previously the problem seemed worse on rainy days. but it was annoying enough even on perfectly dry days that I simply turned off the parking sensor chimes for the past couple months.

the Service Center confirmed this is a known problem - for some reason a batch of cars including mine were built with too much paint on some of the parking assist sensors. I finally had two of the front left sensors replaced today under warranty (it took a while for the parts to arrive and to get an opening for a service appointment). They actually measured the paint thickness on all the sensors, and just replaced the two that were out of spec. I see on the work order that the good sensors all measured paint thickness of 130-140µm. The two bad sensors had paint that measured 155µm and 160µm and so were replaced. Just FYI in case anybody else is seeing this problem.

Mine were bad intermittently in the rear. Thick paint was suspected but was in spec. 2nd visit they replaced the sensors and they've been good ever since. Not sure how or if paint thickness affects AP.