2020 Tesla Model 3 Electrical System Problems

My Tesla Model 3 was brought to Tesla Princeton Service Center on February 27, 2025 for a 12V battery replacement. During the service visit, Tesla also replaced the rear glass, citing the rear defroster as the root cause of the battery drain — a repair that was added without prior discussion and increased the total invoice from an original estimate of $180 to a final charge of $1,730. Upon picking up the vehicle, the rear backup camera, blind spot cameras, navigation system, Sentry Mode, and windshield wiper sensor were all non-functional. None of these systems showed any malfunction prior to the service visit. Tesla Princeton’s service advisor denied responsibility without performing diagnostics, and in a subsequent message admitted he could not determine the cause with certainty without diagnostics — which have still not been performed. The vehicle was discharged from a licensed Tesla Service Center in a condition non-compliant with FMVSS 111. I have escalated this matter to Tesla executive leadership in writing and am filing this NHTSA complaint to create a federal record of this safety violation.

The contact owns a 2020 Tesla Model 3. The contact stated that while the vehicle was parked, the trunk became inoperable. The contact stated that the trunk latch failed to open when the trunk release was engaged using the mobile application, the instrument panel, or the trunk release button. The contact received notification of NHTSA Campaign Number: 21V00D000 (Electrical System, Visibility, Back Over Prevention). The vehicle was taken to the dealer, but was not diagnosed. The contact was informed by the dealer that the cable harness was not repaired and that a zip tie was placed on the cable harness. The vehicle was not repaired. The contact stated that after the dealer visit, the trunk failure persisted. The manufacturer was made aware of the failure. The approximate failure mileage was 69,125.

Software update was pushed onto my car, after the update the car autopilot ECU no longer works. When the ECU finally failed these features were stuck or are completely broken/not working: - Auto dim rear view mirrors (these were stuck in dim mode, preventing me from seeing in rain or darkened environments such as at night or under shade, 0% visibility under these conditions when changing lanes or reversing) - Rear view camera completely stopped functioning, as did all cameras on the car - Forward collision warning no longer works - Autopilot (ADAS features in general) no longer functioning including lane keep assist - On screen navigation is locked in place where the car failed (screen shows location where the car ECU presumably failed). I am further unsure if the following features function as required: - Airbag deployment - AEB (Automatic emergency braking)

Back and buttocks area suffered electrical burns and pain from Tesla Seat Heaters (in heated seats) twice 1. Happened in 2024 on temperature level 3 2 Although I turned it down it happened again in 2025 on temperature level 2

My Motor Control Unit failed. No reason given by Tesla Service Center. It simply just died. They cannot find a reason, and they also said I didn't do anything to cause the MCU to fail. Service Center agrees this is a rare event. Likely got a really faulty MCU to start with. I bought my car in 2020, so just over 4 years later my MCU died.

Found the front body controller to be internally faulted

The Tesla is reflecting an error “DIR_a126” that is reducing the speed below the speed limit and with no rhyme or reason. Tesla services are not available and the problem is intermittent. Additionally, based on research it is found to not have consistent resolutions and reasonings

Car radio goes so loud it damaged my ear nerves. This results in pain especially when exposed to loud sounds

After loading our two children ages 2 and 5 in to vehicle and securing in car seats, the car doors were closed and would not reopen. The children were unable to open the doors themselves. The trunk and other entries did not open. There was no obvious way to open the doors or the issue the car was experiencing. The battery cover would not open. Eventually after I searched the Internet I determined that the 12V battery died (no warning whatsoever, doors worked before loading children) and this caused all occupants to be detained in vehicle as the emergency release is the mechanical means of opening the door and this emergency release is not intuitive or obvious. Within 20 minutes I was able to use an arcane hot wiring method to unlatch a door with a spare 12 V source and a hidden 12 V port not immediately obvious either. Thankfully not in setting of an emergency, not a sunny or excessively warm day and had internet access to research this event. If any of the above were true, life limb and property loss would easily have occurred.

I AM STILL WAITING FOR TESLA TO MAKE THIS REPAIR. I HAVE CONTACTED A SERVICE CENTER SEVERAL TIMES AND TRIED TO MAKE AN APPOINTMENT ONCE. TESLA CANCELLED THE APPOINTMENT AND KEEPS TELLING ME THEY HAVE NOT RECEIVED THE PARTS TO MAKE THE REPAIR. IT HAS BEEN OVER A YEAR AND A HALF SINCE TESLA ANNOUNCED THE RECALL AND IT HAS FAILED TO REPAIR MY CAR. MY UNDERSTANDING IS THAT THE HARNESS CAN SHORT OUT AND CAUSE A FIRE.

The contact owns a 2020 Tesla Model 3. The contact stated that while driving 75 MPH at night with self-driving assist mode, the auto high beams lights engaged three times within 20 seconds. The contact stated that the driver ahead of him then decelerated and veered to the side of the road because it appeared that the contact was sending him an alert through the activation of the high beams. Additionally, the contact was pulled over by a Police Officer. The contact stated that the auto high beam feature was distracting to other drivers. The contact stated that he was unable to disengage the feature. The manufacturer was notified of the failure and informed the contact that the driver did not have control over the feature. The vehicle was not diagnosed or repaired. The failure mileage was approximately 70,000.

The contact owns a 2020 Tesla Model 3. The contact received notification of NHTSA Campaign Number 21V00D000 (Electrical System, Visibility, Back Over Prevention) however, the part to do the recall repair was unavailable. The local dealer was contacted, and it was confirmed that the part was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.

Left headlight blinker and windshield wiper not working. Happened twice once in 2022 and now. Repaired once in 2022 and when happens is dangerous because can’t signal and can’t use wipers in the rain

The contact owns a 2020 Tesla Model 3. The contact stated he was not able to operate the rear windows in the vehicle. The contact referenced his concerns about regulation Federal Motor Vehicle Safety Standard: 571-6; not allowing him to open or close the rear windows. The vehicle was not diagnosed or repaired. The manufacturer had been informed of the failure through the App. The failure mileage was approximately 44,300.

The problem is my car has been in the shop six times for an issue that Tesla claims it is unable to fix. I started smelling a burning smell (smoke coming from my air vents anytime the air is on) and brought it in. The first three times they were unable to find anything the fourth time they noticed debris That was embedded in the heating fins. They replaced that unit. The fifth/sixth time they actually took the HVAC unit out and noticed the entire plastic underneath was melted and warped. Since the smell has continued and I’m worried that it’s dangerous, I had the air quality tested. The formaldehyde levels were 50 times higher than the EPA recommends as a safe level. (HCH0 level of 6 ppm) I’ve submitted all this to Tesla and they said they are currently working with their legal team to figure out if a buy back as possible. The New York Attorney General told me that the car is not viable for a lemon law due to the fact they didn’t do three chances to fix it in 90 days. (The first 2 appointments were in the 90 days but the 3-6th were just past it) The car is not safe to breath air in and my lungs hurt from even spending a few minutes in the car. I’m worried about the effects it has on my health and I feel morally wrong to sell it to anyone else. Please help.

The contact owns a 2020 Tesla Model 3. The contact received notification of NHTSA Campaign Number: 21V00D000 (Electrical System, Visibility, Back Over Prevention) however, the part to do the recall repair was not yet available. The local dealer was not contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue and informed the contact that a request was not needed at this time and that he would receive a notification for an appointment for the recall repair. The contact had not experienced a failure. Parts distribution disconnect.

The car broke down completely saying that "Electrical system failure". It is immobile. This is dangerous as I was driving on the freeway and it suddenly started showing lot of warnings. Warning included "12v power system failure", "Electrical system failure". "Brakes might not work". Somehow I got in to the garage and the car is now immobile. It does not even lock. It is in the same condition as I parked. Cannot open other doors. This could have been life threatening if it had stopped on the freeway. With the price and safety rating, I never expected Tesla to have total failure.

The 12 volt battery on my T2020 Tesla Model 3 failed without warning last week when I entered the driver's side and closed the door. There was a very brief warning on the control screen that the "12 volt battery should be replaced soon." Then the screen went blank and all controls to the car were rendered inoperable. I could not open the door. I had to go on line on my mobile phone to the Tesla website to get the manual to remind myself how to use the mechanical latch on the door. I then exited the car, and could not re-enter the car. My biggest concern is that if a child or an animal were in the back seat there would be NO WAY to get them out without breaking a window. The Tesla technician came the next day to change the 12 volt battery. To do this on a Tesla Model 3, he first had to use an external 12 volt battery to open the "frunk", which he did. However, the car's 12 volt battery was so dead that he could not jump it. He then had to "break in to the car" by inserting a pneumatic pillow into the driver's side window so that he could insert a coat hangar he made himself (he told me Tesla does not supply them!). It took him about an hour of fumbling before he was able to open the mechanical latch on the driver's door; this allowed him to disconnect the main battery unit below the rear seat so he would not be electrocuted when he changed the 12 volt battery in the frunk. So even if I had had a set of jumper cables and an eternal battery at the time the car's 12 volt battery failed, I would have had to break a window to get into the car to rescue a child or animal who might have been trapped in the car. This is clearly a design flaw that should be corrected to improve the safety of a car that I otherwise like very much. I should mention that the Tesla technician said he was seeing a lot of these 12 volt battery failures; he had 4 more to address that very day. Thank you.

Need to ship vehicle to Hawaii however the remedy for the active recall is currently unavailable.

The contact owns a 2020 Tesla Model 3. The contact stated while driving approximately 20 MPH, there was a loud sound coming from the vehicle. There was a warning message to take control of the vehicle displayed. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The contact related the failure to NHTSA Campaign Number: 22V063000 (Electrical System, Forward Collision Avoidance). The approximate failure mileage was 9,800.