I just filed NHSTA complaint number 11365827. In a nutshell: all my exterior lights just turned off while driving on a twisty, limited-access road with no shoulder (Garth Woods section of the Bronx River Parkway, for those of you in the NYC area) in the dark. Head and tail. Neither high nor low beams would come on (high beams wouldn't even "blink" when I pulled the stalk). If a driver behind me hadn't noticed and used his high beams to guide me about a mile onto the next safe shoulder, I could easily have died.
I have to say though Tesla's replaced my MCU once (killed early, probably because an engineer turned on extra debugging trying to root-cause a media player problem - back in the days when you could actually email JonMC and someone actually might tap an engineer on the shoulder and ask them to look at your problem!) I have always thought of the MCU1 failures as a nuisance problem with some, but minimal, safety impact. Yes, you lose the rear-view camera. You might be unable to engage the defroster. But I never expected it to plunge my car into complete darkness (and keep it that way) while I was driving. I simply could not see how this could happen, not believing the MCU controlled the exterior lights.
I've been concerned my MCU (remember, this is the _replacement_, but it is several years old) was failing again, for about a month now. Screen corruption while charging, very long car start up times, weird voice control behavior, etc -- all the stuff I saw just before it failed the first time.
Today when the lights went out, even before I was able to pull over I started MCU, then IC reboots. The MCU took nearly 3 minutes to reboot. When both were online the ICU displayed the "driver assistance features unavailable" message. Other stuff was weird -- for example, the "report" voice control function repeatedly said "That feature is not available yet" after recognizing my speech, then eventually failed further and just started displaying "Microphone calibrating" when I hit the speak button.
Lights all stayed off, would not turn back on. The hazards did work, but that was all.
It finally occurred to me to try to turn on the fog lights via the MCU. Navigating to there I saw that the "exterior lights" setting was AUTO, as I expected. The fog lights actually did turn on! Spent a minute trying to decide if I was willing to try to drive all the way home with just the fogs, then inspiration struck. What if the MCU was displaying AUTO but the actual setting -- either on the MCU or some other controller -- had been corrupted?
I moved the slider to "ON". Nothing happened. I moved the slider to "OFF". Nothing happened. Turned off the fogs to be sure -- nope, no lights. Moved the exterior lights slider back to "AUTO" and...light! Everything came back on as normal.
On the last block on my way home, at about 25MPH, I tested to see what would happen if I turned "exterior lights" off via the MCU while the car was moving at speed. Guess what? They turn off. So the MCU can, in fact, kill your head and tail lights if its notion of how they should be gets screwed up. And, it appears, this is likely what happened to me.
I have no idea how to effectively report this to Tesla. It's a severe safety issue. I could have died. But if I call service I have every expectation that they will do nothing but offer to replace my MCU at my expense, since the vehicle is now long out of warranty. Thus the NHTSA report.
If this happens to you -- since, much to my surprise, clearly it can -- and you can't immediately pull over, as I couldn't, all I can advise is to try to very quickly navigate the MCU to the "lighting" screen and turn the exterior lights off, then on again. It seems to have saved my butt and it might save yours in a much more dramatic way.
I have to say though Tesla's replaced my MCU once (killed early, probably because an engineer turned on extra debugging trying to root-cause a media player problem - back in the days when you could actually email JonMC and someone actually might tap an engineer on the shoulder and ask them to look at your problem!) I have always thought of the MCU1 failures as a nuisance problem with some, but minimal, safety impact. Yes, you lose the rear-view camera. You might be unable to engage the defroster. But I never expected it to plunge my car into complete darkness (and keep it that way) while I was driving. I simply could not see how this could happen, not believing the MCU controlled the exterior lights.
I've been concerned my MCU (remember, this is the _replacement_, but it is several years old) was failing again, for about a month now. Screen corruption while charging, very long car start up times, weird voice control behavior, etc -- all the stuff I saw just before it failed the first time.
Today when the lights went out, even before I was able to pull over I started MCU, then IC reboots. The MCU took nearly 3 minutes to reboot. When both were online the ICU displayed the "driver assistance features unavailable" message. Other stuff was weird -- for example, the "report" voice control function repeatedly said "That feature is not available yet" after recognizing my speech, then eventually failed further and just started displaying "Microphone calibrating" when I hit the speak button.
Lights all stayed off, would not turn back on. The hazards did work, but that was all.
It finally occurred to me to try to turn on the fog lights via the MCU. Navigating to there I saw that the "exterior lights" setting was AUTO, as I expected. The fog lights actually did turn on! Spent a minute trying to decide if I was willing to try to drive all the way home with just the fogs, then inspiration struck. What if the MCU was displaying AUTO but the actual setting -- either on the MCU or some other controller -- had been corrupted?
I moved the slider to "ON". Nothing happened. I moved the slider to "OFF". Nothing happened. Turned off the fogs to be sure -- nope, no lights. Moved the exterior lights slider back to "AUTO" and...light! Everything came back on as normal.
On the last block on my way home, at about 25MPH, I tested to see what would happen if I turned "exterior lights" off via the MCU while the car was moving at speed. Guess what? They turn off. So the MCU can, in fact, kill your head and tail lights if its notion of how they should be gets screwed up. And, it appears, this is likely what happened to me.
I have no idea how to effectively report this to Tesla. It's a severe safety issue. I could have died. But if I call service I have every expectation that they will do nothing but offer to replace my MCU at my expense, since the vehicle is now long out of warranty. Thus the NHTSA report.
If this happens to you -- since, much to my surprise, clearly it can -- and you can't immediately pull over, as I couldn't, all I can advise is to try to very quickly navigate the MCU to the "lighting" screen and turn the exterior lights off, then on again. It seems to have saved my butt and it might save yours in a much more dramatic way.