2018 Tesla Model 3 Fuel system Problems

Potential safety defect: high-voltage battery and battery management system (BMS) appear to overestimate available energy and remaining range, creating risk of unexpected 0% state of charge or loss of motive power without warning. Across 20 documented charge/discharge cycles between January and May 2026, the vehicle has consistently delivered approximately 135-150 miles of real-world range against an EPA-rated 310 miles, under routine driving conditions. The vehicle's own energy display shows observed usable energy averaging approximately 49.93 kWh -- approximately 66.6% of the rated 75 kWh pack. Tesla/BMS diagnostics report approximately 79-80% pack retention, implying approximately 58-59 kWh available -- approximately 8-9 kWh more than the vehicle's own consumption display reflects. No BMS fault code, low-power alert, or driver warning has been generated despite this persistent discrepancy. On April 22, 2026, after a drive, the vehicle was parked showing approximately 3% SOC and 7 miles remaining. Approximately five hours later, while parked and not being driven, the vehicle displayed 0% SOC and 0 miles. No fault or warning was triggered. Supporting photographs document the same low-SOC discharge cycle: vehicle at 27%/65 miles on April 20 and at 0%/0 miles on April 22. A driver relying on 3%/7 miles as a margin to reach a charging location could become unexpectedly stranded. If a similar BMS recalculation occurred while driving at low SOC, the result could be sudden unexpected loss of motive power -- a potential roadway safety hazard before the driver receives adequate warning. On May 14, 2026, Tesla Service performed a battery health review (Invoice 3000S0016915237) documenting 79% pack retention, no faults found, no further action. Test name, methodology, and whether the review evaluated BMS calibration accuracy or low-SOC energy availability were not disclosed.

NHTSA ID

11738357

Incident

Apr 22, 2026

Tesla failed to properly diagnose a high-voltage battery isolation fault in my 2018 Model 3. Despite safety-critical BMS_a027 and BMS_a142 faults indicating multiple isolation failures, they skipped required insulation resistance testing, falsely blamed sand in a connector, and charged me $174.95. After the issue returned, they reversed course, replaced an internal battery contactor, and reduced the $1,173 estimate to $356—admitting fault without owning it. Days later, a diagnostic showed dangerously low isolation resistance (380kΩ, far below Tesla's 1,000kΩ safety threshold), yet they took no further action. On July 12, the car again went into limp mode. Tesla’s repeated failure to follow safety protocols, diagnose accurately, and honor warranty obligations has left me with a vehicle in an unsafe state and no corporate accountability. I've contacted their Resolutions team three times (7/2, 7/7, 7/10) with zero response.

NHTSA ID

11673763

Incident

Jun 11, 2025

Power Conversion System (PCS) failed Doesn’t allow car to charge. Car has only 33k Miles on it.

NHTSA ID

11655709

Incident

Apr 18, 2025

1. PTC Heater, old part is available for inspection 2. PTC heater failed while driving, experienced loss of power and slow loss of secondary electrical systems (the 12v battery was not able to recharge itself with the PTC heater not functioning). When attempting to restart car after pulling into a parking lot, the entire car died (12V battery was drained so it couldn't start up) and had to get towed to Tesla service center. PTC heater is critical for car to operate as it is closely linked to 12V battery. Additionally, without PTC heater car cannot defog windshield, resulting in potentially poor visibility. 3. Dealer replaced the defective part (PTC heater) and had to replace 12V battery as well. Was not covered under warranty and I had to pay the cost out of pocket. 4. Inspected by manufacturer and replaced. 5. Got warning signs about reduced power available, and secondary electrical features were limited.

NHTSA ID

11652498

Incident

May 12, 2024

1. The Power Conversion System (PCS), still in the vehicle and not available for inspection 2. 2 of the 3 controllers have failed, resulting in limited AC charging (16A out of 48A max). The PCS helps regulate AC and DC electricity and connects the 12V batter to the HV battery. If it fails, it could lead to dangerous situations since the electricity from the HV battery wouldn't be as controlled. I'm worried that if the final controller fails while driving it could lead to a loss of power. 3. Problem throws an error code when charging that the dealer has verified, they will not replace it unless I pay for the part+labor which is roughly $1,800. 4. Vehicle inspected by dealer, they will only fix if I pay for replacement part. 5. Car has warning message when charging.

NHTSA ID

11652488

Incident

Mar 1, 2024

I was at a stoplight behind a Toyota Tacoma. I must have stopped around 8 feet behind it. I was not using FSD and I was not one-pedal driving. My foot was on the brake. I must have been at a complete stop for approximately 10 seconds when my Model 3 suddenly accelerated full throttle on its own and rear ended the Tacoma, directly hitting its trailer hitch, causing my car's driver-side airbags to deploy. When it happened, the light was still red and my foot was still on the brake. I never touched the accelerator. Luckily I was driving alone. After the inital contact, my car sort of bounced off of his hitch then slowly lurched forward before it stopped. After that, it was immobile, leaving me stuck in traffic until it was towed away.

NHTSA ID

11632896

Incident

Dec 19, 2024

Salt Lake City Tesla Service Center 801-401-4135 I purchased a 2018 Tesla Model 3 Long Range AWD, VIN [XXX] . The car’s battery and motor drive train units are still within the warranty. On [XXX], the car’s POWER CONVERSION SYSTEM (PCS) stopped working spontaneously, without any physical damage caused by the owner. The PCS is required to charge the car. A broken PCS rendered my car essentially unchargeable, thus undriveable, and unusable. The PCS is a critical component required for normal car function. Without a functioning PCS, you have a broken car. This is a SAFETY ISSUE because you can be stranded in the middle of nowhere without the ability to charge and safely extract yourself from inclement weather and environmental exposure. On [XXX], I transported the car all the way from Pocatello, the 169 miles to the nearest Tesla Service Center in Salt Lake City, UT, at my own expense. On [XXX], the car was diagnosed, and repaired. On [XXX], before paying for the repair, I spoke to the Tesla Service center manager because I felt this component failure should have been covered under the warranty because it represents a FAILURE of a CRITICAL COMPONENT. This is a safety risk, as I mentioned above. He expressed sympathy with my situation and said that broken PCS was a known issue in early Tesla Model 3’s. After doing some research, this is indeed the case, with many online complaints about a broken PCS in Tesla Model 3’s. He said he hoped Tesla would some day reconsider, and that a retroactive reimbursement was in the realm of possibility, as has been done in the past for various component failures in Tesla vehicles. Overall, my grievance with Tesla is that a broken PCS is a CRITICAL FAILURE of a component REQUIRED to have a functioning, chargeable car, and it is a component with a KNOWN HIGH RATE OF FAILURE in Tesla Model 3’s. This should be covered by the battery and drive train warranty. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11578462

Incident

Feb 7, 2024

The Power conversion system (PCS) failed during driving, disabling the rear motor and regenerative braking. This severely affected the driving characteristics of the vehicle, including top speed, braking profile and handling.

NHTSA ID

11556810

Incident

Nov 23, 2023

My Tesla Model 3 without any warning stopped working suddenly. I could not put the car in drive and there were error messages about climate control and electrical system. I had to get the car towed to the service center as it was blocking my other car in the driveway. The service center in Sunnyvale, CA diagnosed the problem to be a faulty PTC heater and has charged me over $1100 to replace it. I beileve it is quite absurd to have a fault in the HVAC system render the whole vehicle completely immobile and useless. This seems like a serious design flaw and it could lead to serious health or safety concerns.

NHTSA ID

11515708

Incident

Apr 2, 2023

PCS Charger (Onboard) is failing on numerous early build Model 3 cars (2017-2019). Telsa is claiming that this is not included in battery warranty, however Tesla's own service manual shows this part specifically in the HV Battery System. I still have the fault PCS charger in the car, it is limited to 32Amps but several forums and webpages state its only a matter of time before I am limited to 16Amps The car is unable to charge at a reasonable recovery rate in which you can even use the vehicle for it's intended purchase. Tesla has acknowledge it's failure but is unable to produce actual number of failed units. The warning lamp had been displaying "dirty electrical grid" for quite some time until I was able to search the internet for the exact issue.

NHTSA ID

11503192

Incident

Nov 25, 2021

On December 27, 2022, in light evening street traffic, my car accelerated briefly without the accelerator pedal being applied. I took my foot off the accelerator pedal to decelerate for an upcoming red light. While my foot was off the pedal, the car accelerated and lurched forward. The car was towed to the Tesla Sacramento Service Center. The technician incorrectly cited the "creep mode" as being involved. The car was in motion when it unexpectedly accelerated. "Creep Mode" only engages when the car is close to or fully stopped. Tesla technician was unable to determine an accurate reason for the unexpected acceleration.

NHTSA ID

11502032

Incident

Dec 27, 2022

The Power Conversion System is failing, this makes charging the car difficult. The charge rate is reduced and charging fails without warning. There is no warning from the vehicle that the part is failing but instead says the power grid is the issue. The issue started while the car was still under warranty, but falsely claimed the problem was with the evse or the wiring to the evse. Had the failure been properly reported rather than being misleading, the vehicle could have been repaired under warranty,

NHTSA ID

11501150

Incident

Sep 1, 2022

I reported charging problems over the last several months to Tesla. You can only report problems via the App. They do not provide a phone number. They tried to fix my charging issue three times and each time said it was fixed. It was not and today I almost ran out of battery on the interstate because it would not charge. Today, after waiting an hour for their roadside service to respond they came and towed it. This is the fourth attempt to fix it.

NHTSA ID

11490484

Incident

Oct 23, 2022

Originally received notification of DTC "BMS_a035 - Vehicle may not restart." Vehicle was serviced and the rear motor drive unit was replaced. Was not given the oppertunity to inspect the serviced components upon request. Within 48 hours of service, "BMS_a027: Power limited, OK to drive," & BMS_a170 - (de)acceleration warning & top speed warning." My concern is related to a potential cascading problem, which cannot be diagnosed, and which will lead to failure of the propulsion system or an unexpected discharge issue / thermal event from an electrical issue while the vehicle is in use and/or parked.

NHTSA ID

11485819

Incident

Sep 7, 2022

For a growing number of Model 3 owners, components in the HV Battery Service Panel are breaking down, yet Tesla refuses to cover the repair under its Battery and Drive Unit Warranty. Specifically, the "power conversion system" (PCS) in that panel is failing, and reducing an AC charge from 48A to 32A to 16A to… zero. If an owner drives to a location to charge from a Level 1 or Level 2 charger, and the PCS has failed, that owner will be stranded, unable to operate the vehicle. I have submitted a request for mediation to the American Arbitration Association (case no. 01-22-0001-9026), but I deem it important to not only address the problem in my vehicle, but all the others experiencing this same breakdown. I am thus reporting it to NHTSA, as I purport that a recall is in order. I will attach a more detailed description of my dispute with Tesla, as well as my original Purchase Agreement with an Agreement to Arbitrate, and a copy of Tesla's most recent warranties.

NHTSA ID

11464156

Incident

Jan 1, 2022

The vehicle looses power on the freeway and will continue to slow down despite repeatedly depressing the accelerator and holding it down. The vehicle has been brought in to Tesla and no fix has been found to this date. No warning lights go on and sounds are heard to alert to any problem. I have video of this.

NHTSA ID

11456770

Incident

Feb 23, 2022

I needed to back up slightly to make room to get our of a parallel parking position. I pressed the brake and put the car into reverse, pressed the accelerator slightly to back up. I then pressed the brake again and put the car into Drive. I then pressed the accelerator slightly to drive off, but the car suddenly accelerated in an uncontrolled manner. I was able to slam on the brakes to prevent an accident. This is not the first time that this type of unintended acceleration has occurred in this vehicle.

NHTSA ID

11455066

Incident

Mar 3, 2022

When driving with the driver assist Auto Pilot active it's possible to disengage Auto Pilot but Traffic Aware Cruise Control (TACC) remains active. When Auto Pilot is active the auto pilot system has control of the car including navigation, maintaining the lane, and speed. Speed can be set by the car or driver. In some cases disengaging auto pilot disables TACC , in other cased TACC remains active. A driver may be caught off-guard when the car continues forward at the set speed after disengaging auto pilot. This difference in behavior can surprise a driver and that puts every other driver in the area at risk. Ways to disengage Auto Pilot : 1) Press up on the right-side stalk (also used to engage TACC & Auto Pilot) on the steering column behind the steering wheel. When pressing up on the stalk Auto Pilot and TACC are both disabled. 2) Step on the brake pedal. Pressing the brake pedal disables both Auto Pilot and TACC. 3) Turn the steering wheel, for example to avoid a road hazard or a vehicle in the car's path. Turning the steering wheel only disables Auto Pilot functions, TACC remains active. The car continues to move forward at the speed Auto Pilot was using. The three disengagement methods have similar, but different outcomes. The result is a driver by moving the steering wheel can disengage Auto Pilot while cruise control remains active. This problem is compounded when considering Tesla's forward collision warning and avoidance has issues with stationary vehicles like those stopped at off ramp traffic lights or in traffic jams (this will be covered in another report). Since cruise control remains active when Auto Pilot is disengaged by turning the steering wheel is as designed there are no warnings or alerts. Several time I've had to swerve or slam the brakes to avoid contact with other cars and trucks after taking control with the steering wheel while Auto Pilot was active. This happened several times, date listed in Additional Details is near first time.

NHTSA ID

11447975

Incident

Mar 12, 2019

Power Conversion System was defective when car brand new and replaced under 50k mile warranty. Now out of 50k mile warranty and Power Conversion System is failing again. Manufacturer service center says this item is customer pay and is just a defective item that is out of warranty for the 1-year replacement warranty, and refuses to cover this repair under the battery warranty where the Power Conversion System is located. Service center states there is nothing the customer did wrong or could do to cause this problem, acknowleges it is a defective part, and insists it is customer pay with no indication of an updated part. What happens when the Power Conversion System fails is the car is stranded and cannot recharge or operate its safety systems. This should be a recall item if it was updated to a newer part correcting defective design. The manufacturer should replace this high voltage and core functionality of the vehicle under its battery warranty where the part is located. It would be highly dangerous for the vehicle owner to replace this part and requires specialist tools to diagnose and replace or repair.

NHTSA ID

11437904

Incident

Nov 18, 2018

My car was parked and was charging in our garage when it suddenly shut off. I got into the car to get something, but noticed the car's computer screen did not light up. I tried to open the glove box and it also would not open. When I tried to open the car door button, it also would not open the door while I was still inside. I got out of the car using the manual car handle and realized the charger would not unplug from the car either. I was very scared that the car was going to burn because the battery was charging at the time and everything suddenly happened. In addition, the backseat doors do not have a manual car handle to open the door. In an event of an emergency and the power shuts off, how are passengers sitting in the backseat going to escape from the vehicle??? The cause was due to a 12v battery malfunction.

NHTSA ID

11419435

Incident

Jun 1, 2021

UNINTENDED ACCELERATION RESULTING IN A CRASH WITH A TREE. MY CAR WAS TOTAL. THE CAR WAS WAS STATIOANARY WAITING TO PUT AIR IN MY TIRE.

NHTSA ID

11396564

Incident

Oct 16, 2020

Mileage

1,700 mi

THIS IS A COMPLAINT ABOUT A BURNED OUT TESLA MODEL 3. I HAVE USED THE VIN OF A RANDOM WRECKED TESLA BECAUSE THE VIN OF THE CAR IN QUESTION IS UNRECOGNISABLE DUE TO FIRE. HERE IS THE TOASTED TESLA HTTPS://WWW.IAAI.COM/VEHICLEDETAILS/35451122/25 IT HAS BEEN BURNED TO A CRISP BUT THE FRONT WHEEL HAS BEEN WRENCHED OFF DUE TO THE USUAL BROKEN SUSPENSION ARMS AND POPPED BALL JOINTS. THE WHEEL MUST HAVE FALLEN BY THE WAYSIDE BECAUSE IT IS NOT BURNED IN THE SLIGHTEST AND HAS BEEN STASHED INSIDE THE BODY OF THE CAR POST-INFERNO. ISN'T THE JOB OF NHTSA SUPPOSED TO BE PROTECTING THE PUBLIC? WHAT IS WRONG WITH YOU GUYS? FOR THE LOVE OF FUDGE PLEASE DO SOMETHING. REGARDS YOUR FRIEND KEEF

NHTSA ID

11311515

Incident

Feb 1, 2020

Mileage

20,000 mi

ON 04/13/2019 THE CAR ABRUPT STOPPED IN THE MIDDLE OF THE ROAD WHILE I DROVE IT ALONG NORTHBOND SANTA RITA ROAD IN PLEASANTON CA. . CARS COMING FROM BEHIND HAD TO MAKE URGENT BRAKING OR LANE CHANGE TO AVOID HITTING US. MY YOUNG CHILD WAS CRYING IN HORROR, AND WE HAVE NO WAY TO GET OURSELF TO SAFETY WITH THE CAR TOTALLY UNABLE TO MOVE. WE CALLED 911, AND LOCAL POLICE WAS DISPATCH TO HELP OTHER CARD AVOIDING HITTING US, WHILE WE WAITING FOR TOW TRUCK TO ARRIVE. THE CAR WAS UNRESPONSIVE FOR ABOUT 20 MINUTES, WITH THE DISPLAY SHOWING MESSAGES: "UNABLE TO DRIVE, PULL OVER TO SAFETY. CAR SHUTTING DOWN". THE CAR RESUMED OPERATIONAL AFTER ABOUT 20 MINUTES, WITHOUT ANY NOTICEABLE CHANGE. I DROVE THE CAR TO NEAREST SERVICE CENTER (PLEASANTON CA). AFTER A FEW DAYS, I WAS CONTACT BY THE SERVICE CENTER STATING THE CAR CAN BE PICKED UP, WHILE NOTHING WAS DONE TO FIX THE ISSUE. THEIR OFFICIAL INVOICE STATES: "THIS IS CURRENTLY SCHEDULED TO BE FIXED IN 2019.20, BUT THE CUSTOMER CAN CONTINUE DRIVING. IF IT HAPPENS AGAIN (SEEMS UNLIKELY), THEY CAN JUST GET OUT OF THE CAR AND GET BACK IN TO RESUME OPERATION.". I POINTED TO TESLA SERVICE REPRESENTATIVE THAT THEIR RECOMMENDED SOLUTION IS UNACCEPTABLE - JUST LIKE WHAT HAPPENED TO US ALREADY - IT WOULD BE ILLEGAL AND UNSAFE TO EXIT THE VEHICLE IF IT STOPS IN THE MIDDLE OF HIGHWAY, WITH NO CHANCE TO PULL OVER EVEN TO THE CURB. THE TESLA REPRESENTATIVE BROUGHT AN ENGINEER TO HELP "EXPLAIN" THE INFORMATION, WHEN HE MENTIONED THAT THIS ISSUE IS A KNOWN CHARACTERISTIC RELATED TO USE OF CRUISE CONTROL. AND THE ENGINEER SAID HE WOULD PERSONALLY BE OK TO DRIVE THE CAR WITHOUT USING CRUISE CONTROL. I ASKED IF THAT MEANS THE CRUISE CONTROL IS NOT SAFE, THEY SAID IT WOULD BE MY OWN JUDGMENT. I THINK THIS IS A SIGNIFICANT SAFETY HAZARD TESLA IS INTENTIONALLY IGNORING AND NEED THOROUGH INVESTIGATION.

NHTSA ID

11203847

Incident

Apr 13, 2019

Mileage

13,350 mi

THE VEHICLE WAS PARKED. BUT WOULDN'T MOVE TO GEAR (DRIVE OR REVERSE). IT WAS GIVING THE MESSAGE "CANNOT MAINTAIN VEHICLE POWER". HAD I LOST THE POWER WHILE DRIVING, IT WOULD HAVE BEEN A CLEAR SAFETY ISSUE.

NHTSA ID

11180376

Incident

Feb 8, 2019

Mileage

1,500 mi