2021 Tesla Model 3 Electrical System Problems

The vehicle is undriveable due to a high‑voltage enable safety lockout triggered by ECU identity/MAC mismatch after a software/update window; local service instructed me to ‘safely disregard’ active safety alerts contrary to vehicle telemetry, creating a safety risk. Chronology (key timestamps) • Jan 28, 2026 — Low‑voltage undervoltage precondition recorded (DIF_a018). • Feb 2nd, 2026 — Low‑voltage undervoltage precondition recorded (DIF_a018). • Feb 03, 2026 08:46 — Identity/MAC invalidation alerts (CP_a089 / CP_a077); HV‑enable blocked cascade. • Feb 24, 2026 — Service app: estimate approval prompt; supervisor instruction to ‘safely disregard’ active HV alerts captured via screenshot. • Feb 27, 2026 — Persistent handshake stall (CP_a066, State B1) despite ‘successful’ software job and new firmware update to patch the 2026.2 tree branch software. Vehicle remains grounded. Safety Concern Vehicle telemetry states HV contactors are blocked to protect the vehicle; service staff advised to disregard active alerts. Inconsistent guidance risks unsafe operation. I grounded the vehicle pending engineering review. Troubleshooting and A/B Tests My home EVSEs successfully charge a different Tesla (Model Y). The subject VIN charges at DC fast charging (Supercharger) and once on a third‑party EVSE, but fails on my two home EVSEs thereafter. This localizes the issue to vehicle‑side AC charge path/charge‑port logic rather than the EVSE. Request OEM to provide CP waveform under load + Toolbox logs. Please log this safety‑related defect; aggregate with similar complaints, and, if appropriate, open an investigation into identity/integrity faults causing HV‑enable lockouts and conflicting service guidance

To Whom It May Concern, I am submitting this complaint to report a serious and potentially dangerous safety defect affecting my 2021 Tesla Model 3 Performance. After exposure to heavy rain or wet conditions, the vehicle’s horn completely stops functioning. The failure occurs regardless of the activation method—neither pressing the steering wheel horn nor using the horn via the mobile app produces any sound. The horn remains nonfunctional even though the vehicle is otherwise operable. This issue has occurred after the vehicle becomes wet due to rain and appears to be related to moisture intrusion or an electrical/design flaw. Once the failure occurs, the driver fully loses the ability to use the horn for warnings or emergency signaling. This is a critical safety concern. The horn is a federally required safety device and is essential for alerting pedestrians, cyclists, and other drivers to avoid collisions. Losing horn functionality significantly increases the risk of accidents, especially in urban driving, highway merging, and emergency situations where immediate warning signals are necessary. This issue is not isolated to my vehicle. Numerous Tesla owners have reported the same horn failure after rain or wet conditions on online forums and owner communities, indicating a widespread and systemic defect rather than isolated wear or misuse. Given the safety implications and the volume of similar reports, I respectfully request that NHTSA investigate this issue to determine whether a design or manufacturing defect exists and whether corrective action or a recall is warranted. Thank you for your attention to this matter. Owner – 2021 Tesla Model 3 Performance

I have been very cautious on charging my Tesla Model 3 and have followed all of the manufacturer's recommendations. The HV battery recently failed at 105,050 miles. South Korea has noted a battery reliability issue for this year car and model, so I am reporting this to you so if a recall is needed, you can track this. I believe my battery is a Panasonic NCA.

Central computer (motherboard), cameras (front/rear/side), autopilot/auto steer system. Error code: APS_w132. Description of Problem: On or around [XXX], Tesla pushed a mandatory over-the-air software update to my vehicle. Immediately after, multiple safety-critical systems failed: all cameras (including backup) became intermittent or non-functional, auto steer/autopilot stopped working, and the car emitted constant distracting beeping alerts due to a critical motherboard failure. This made driving hazardous—impaired visibility for parking/reversing, loss of collision avoidance features, and constant audio distractions that could lead to accidents. I had to drive in this unsafe condition for weeks while waiting for service. Tesla attempted a remote fix but it failed. I scheduled service on November 19 for December 3 (19-day delay). Diagnostics confirmed the update induced the hardware failure, a known issue reported by other 2021 Model 3 owners on forums like Reddit (e.g., software bricking motherboards post-update). Despite this, Tesla refused warranty/goodwill coverage, quoting $2,576.83 for repairs. Service advisors Josh and Andy were unprofessional: Josh was rude/condescending; Andy was aggressive, sarcastic, and retaliatory. After I mentioned filing complaints with the AZ Attorney General and News Channel 3, Andy threatened $100/day storage fees with an impossible deadline (called at 4 PM Friday, close at 5 PM, demanded pickup by morning, then noon). He closed my ticket without authorization, delaying fixes and forcing me to contact another location—prolonging my exposure to the unsafe vehicle. This defect poses serious safety risks: sudden loss of cameras/autopilot could cause crashes. Tesla's awareness (from prior reports) and poor handling (intimidation delaying repairs) exacerbates the danger. No crash/injury yet, but potential is high. Please investigate this update-induced failure as a widespread defect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Resistive occupancy sensor consistently failing causing: -Bluetooth to not automatically connect anytime the vehicle is entered - vehicle puts itself in park to prevent rollback if seatbelt is not applied - car does not recognize when driver is in seat These are serious safety concerns as it could cause a domino effect in safety features if not applied when needed.

Attempting to park. Slowly inching forward while turning left. Vehicle accelerated. (Sudden Unintended Acceleration: SUA) Vehicle jumped a curb, bounced off a tree, dropped off the curb before comping to a stop. Internet search shows other similar reports; attributed, by Tesla, as pedal misapplication. This was not "pedal misapplication". I am not looking for anything. But NHTSA should increment occurance counter by 1. Tesla has a problem. Electrical or Mechanical...do not know. They have also lost me as a customer. The car will be sold. I have video...mp4

Vehicle Info: Make: Tesla Model: Model 3 Year: 2021 Incident Date: April 7, 2025 Mileage: 49,000 miles Component: Electrical System / Software / Powertrain While driving on a public road, my Tesla Model 3 experienced a total system lag and shut down unexpectedly. The screen and vehicle controls froze, and the vehicle became unresponsive, leaving me stranded in the middle of the road. Tesla service later stated that the car computer had “slow FPS” (frames per second), which they claim caused the issue. They cleared memory, updated firmware, and said no further diagnosis was needed. However, no root cause was provided, and I am concerned that this issue could reoccur. This kind of unexpected shutdown while driving is a serious safety concern. I was lucky to avoid a collision, but if this had happened on a freeway or near traffic, the outcome could have been worse. I am filing this report in hopes that NHTSA will investigate whether this is an isolated issue or part of a broader safety defect related to Tesla's onboard software or power management systems.

The contact owns a 2021 Tesla Model 3. The contact stated while driving at various speeds, the hood opened unintentionally, the A/C unit and the radio intermittently turned on and off, the infotainment system screen intermittently turned black and randomly turned back on, along with several other failures that occurred. No warning lights was illuminated. The failures occurred on several different occasions. The contact was notified that the VIN was included in NHTSA Campaign Number: 24V554000 (Latches/Locks/Linkages, Electrical System) however, while attempting to update the vehicle software, the vehicle failed to complete the software update. The vehicle was drivable and was taken to the place of residence; the contact attempted to get in contact with Tesla Roadside Assistance however, once the contact reached the "confirm pickup spot" screen, the screen froze and would not confirm the request. The vehicle was not repaired. The contact attempted to notify the manufacturer however, the contact received no response in return. The failure mileage was unknown.

I am writing to file a formal safety complaint regarding a critical malfunction that occurred with my Tesla Model 3 on [XXX], in West Palm Beach, Florida. This incident raises significant concerns about the safety and reliability of Tesla vehicles, particularly following software updates. Incident Overview: On [XXX], around 5:00 PM, I placed my French Bulldog in the back seat of my Tesla Model 3 and closed the passenger side rear door. As I walked around to the driver’s side, all the doors locked automatically, and I was unable to open any of them. Despite multiple attempts to unlock the car using both my iPhone and key fob, the vehicle remained locked. My dog was trapped inside the car, and I became increasingly panicked, especially considering the extreme summer heat in Florida. I immediately contacted Tesla customer service, but after a 15-minute conversation, they were unable to unlock the car remotely. I was forced to call 911, and the fire department had to break the passenger side window to retrieve my dog. Even after the window was broken, the doors still wouldn’t unlock, and I had to pull my dog out through the shattered glass. Additional Details: The car was charged to 80% just a couple of days before this incident. After this incident, the car is completely dead. It is non-functional, and I cannot power it on or access any of its systems. The day before this incident, I completed a software update on my Model 3, which I believe may have caused or contributed to the malfunction. There is CCTV evidence of the entire incident, which I can provide upon request. My dog was severely traumatized by this experience and is now fearful of being in the car, even when it is parked in the garage. I was also extremely distressed during the incident, and the situation could have resulted in a much worse outcome. Please advise on the next steps for an investigation, and let me know if you require any further information or evidence. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2021 Tesla Model3. The contact received notification of NHTSA Campaign Number: 24V554000 (Latches/Locks/Linkages, Electrical System); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was contacted but saw no recall information related to the VIN. The manufacturer was not made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.

While driving, no warning, car went dead, no control over lights, windows (can’t use hand signals), power steering, unclear if parking brake worked. Had towed. 12v battery died. No explanation as to why there was no warning.

My vehicle is 3 years old and has roughly 52000 on it. After a recent software update (within the past month or so) all of the automatic safety features such as automatic braking, blind spot monitoring, cruise control stopped working on the vehicle. I brought it to Tesla and they confirmed the issue and said the entire ECU needs to be replaced, a $2700 expense on a 3 year old car. There is a warning message every time I start the car that says the automatic breaking is not working.

UNKNOWN

Complete computer failure leaving cars safety systems not working. Had to pay 3000$ for a new computer for a new car. Did not have car for three weeks. No systems would work.

Car was charging in garage overnight when an interior dash electrical fire started. Fire burnt dash and smoke damaged the interior or car. Fire smoldered itself out, and car was considered a total loss. Collision center that picked up vehicle stated that they believed the fire started from an electrical charging fault at the harness in the dash.

I was driving to work that all of sudden heard warning sound and the monitor displayed the "Shutdown" sign as well. The car lost its power and came to complete stop in the middle of the street. Luckily there was no car near me. I was not able to drive the car and had to tow it to the dealership. According to mechanic “the rear drive unit has failed internally”. This was extremely scary and dangerous and may have caused a fatal accident. The problem has been fixed.

I was driving home from work on a two-lane highway when my car suddenly (and without any warning) lost all driving power and shut down while there was still battery left on the vehicle (roughly 10%). I could no longer maneuver the vehicle due to lack of propulsion, so my car died in the middle of the road. It was towed directly to Tesla service center where diagnostics were supposedly run. Their conclusion was the car died due to insufficient charge (even though there was about 10% battery left at the time of the incident). About a week later, the same EXACT thing happened! The car lost all power and shut down mid-drive without any warning with about 7% remaining. Both times, I had my home address in the car GPS (so it knew the exact distance I was traveling) and it never indicated once that I needed to stop and charge the battery. Again, I had the car towed to the service center where they reached the same "conclusion" that the car died due to simply running out of battery. When I showed them proof (pictures and videos) that the car died with charge left on the battery, they did not investigate the issue further. They simply stuck to their original conclusion and no longer wanted to help remedy my defective battery. I have video and pictures proving that my car dies without warning (on multiple occasions) while there is still charge left on the battery, but Tesla refuses to fix/warranty my car (let alone try to investigate or replicate the issue). They tell me that my car is "operating as intended" and is safe to drive, all the while knowing it is definitely not safe to drive. I'm especially concerned due to the fact that I drive my two daughters in my car. They both are very young and use car seats. What happens in the event that I am driving on the interstate with them in the backseat and my car randomly dies without warning? There would be no way to safely remove them from the vehicle (let along myself) before being involved in a serious high-speed accident.

While the car was parked in a parking lot, I get two notification stating “Sentry mode has turned off due to a sentry system error.” When I checked out the car, the car has completely failed to do any of the computer related task, leaving only the gear, AC, and Bluetooth was working. None of the cameras, GPS, sensors, brightness mode and many others were completely stuck. This continued until the next day. This happened without prior symptoms or warnings. I would have been in deep trouble if I have been driving at the time of the incident. When I took the car to the shop, tesla didn’t update the status for a week. After a week, Tesla told us that the Turbo A, Autopilot main processor chip failed. This caused the autopilot to go on loop. Therefore the whole motherboard needed to be replaced. This happened to a brand new purchased Tesla 2021 standard range. Which cost me $2404.00.

Electrical system rebooted in the middle of driving: screen went off couldn't signal i swayed to the side and waited till the screen came back on after 3 minutes.

This same event has happened to me approximately 3-4 times since owning the vehicle. It occurs randomly without warning. The vehicle screen will randomly and suddenly freeze up and render itself inoperable. Eventually, the screen will reset itself or I will have to manually force a reset. After about 5-10 minutes, the screen will reset and the problem goes away. During the 5-10 minutes of the screen not operating, I cannot see or change any of the vehicles controls; loss of HVAC control, cannot turn on windshield wipers, cannot see vehicle speed, don't know if turn signals are on/off (also lose audible sounds when turn signals are on) are the major safety related losses; you essentially lose all control over the vehicle settings/controls. Vehicle continues to drive as normal, and all functions are restored after reset is complete.