2020 Chevrolet Sonic

Owner complaints

What owners report most

1. Electrical system6
2. Power train3
3. Engine2
4. Steering1
5. Air bags1
6. Unknown or other1
7. Fuel/propulsion system1
8. Seats1

Latest complaints

• Jun 22, 2026TX
  Engine
  Engine Cooling System (Thermostat Housing / Water Outlet) The vehicle suffered a premature structural failure of the factory engine coolant thermostat housing. The component, which is manufactured from a fragile plastic composite, cracked completely open without warning, causing an immediate, rapid…

  Engine Cooling System (Thermostat Housing / Water Outlet) The vehicle suffered a premature structural failure of the factory engine coolant thermostat housing. The component, which is manufactured from a fragile plastic composite, cracked completely open without warning, causing an immediate, rapid loss of engine coolant. This constitutes a severe safety hazard. A sudden, catastrophic loss of engine coolant under normal driving conditions puts the vehicle at immediate risk of severe engine overheating and sudden engine stalling or seizure while in motion. If the engine stalls unexpectedly in high-speed traffic, it strips the driver of power steering and braking assistance, drastically increasing the risk of a serious collision. General Motors is fully aware of this pervasive material defect across the Chevy Sonic model years, yet they refuse to issue a safety recall, forcing owners to operate vehicles with inherently flawed, dangerous plastic cooling components. They also refuse to help in getting the vehicle repaired or share the cost.

• Nov 1, 2025IN
  Electrical system
  Purchased from Carvana. Nine days after purchase came out to a dead battery took it to the authorized dealer and they said the battery was a bad cell battery. Replace the battery. Six days after they replaced the battery it was dead again. This time they had it in the shop for two weeks before they…

  Purchased from Carvana. Nine days after purchase came out to a dead battery took it to the authorized dealer and they said the battery was a bad cell battery. Replace the battery. Six days after they replaced the battery it was dead again. This time they had it in the shop for two weeks before they found the issue. It had been aftermarket wired with a GPS tracking system that was draining the battery. They said if I have any further issues with it, I need to take it to a dealer. They gave me a bag full of multiple components that had been added to the vehicle. I do not know how Carvana missed them all.

• Nov 15, 2024CT
  Seats
  1. What component or system failed or malfunctioned, and is it available for inspection upon request? The passenger seat adjustment mechanism has failed, causing the seat to become stuck in the farthest rear position. The malfunction is likely related to either the motor, seat track, or the…

  1. What component or system failed or malfunctioned, and is it available for inspection upon request? The passenger seat adjustment mechanism has failed, causing the seat to become stuck in the farthest rear position. The malfunction is likely related to either the motor, seat track, or the electrical system controlling the adjustment. The seat is available for inspection. 2. How was your safety or the safety of others put at risk? The stuck seat presents a safety hazard because it is positioned too far back, which can prevent proper seating posture or seatbelt positioning for a passenger. This could increase the risk of injury in the event of a crash, as the passenger may not be secured properly or may be too far from the airbag deployment zone. 3. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, the issue has been confirmed by both an independent mechanic and two other individuals knowledgeable about cars. The problem has been physically inspected, and the seat remains stuck in the rear position despite attempts to adjust it. 4. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? No, the vehicle has not been inspected by the manufacturer, police, or insurance representatives yet. However, it has been looked at by independent service providers, who have confirmed the issue with the passenger seat. My car is no longer secure by the bumper-to-bumper warranty despite only having 52K millage. 5. Were there any warning lamps, messages, or other symptoms of the problem prior to the failure, and when did they first appear? There were no warning lamps, messages, or other symptoms prior to the failure. The issue with the seat adjustment occurred suddenly, with no prior indication that there was a problem.

• Jul 28, 2024TX
  Electrical system · Fuel/propulsion system · Unknown or other

  Having trouble with leaks and the evap purge system. I repaired it three times. The vehicle will turn off while driving.

• Mar 9, 2024AZ
  Engine · Power train
  1st occurence at approximately 37k miles on Vehicle has issue based on climate temperature sensor triggers a computer code 84 vehicle goes into limp mode to prevent engine failure however, this happens instantly no time to react and more than one occasion creating a hazardous driving situation in…

  1st occurence at approximately 37k miles on Vehicle has issue based on climate temperature sensor triggers a computer code 84 vehicle goes into limp mode to prevent engine failure however, this happens instantly no time to react and more than one occasion creating a hazardous driving situation in heavy traffic, vehicle also overheats creating hazardous leaks of anti freeze at boiling temperatures ability to burn anyone who comes in contact. This remains an ongoing issue with vehicle, vehicle now back in possesion of bank Santander Consumer USA, this is being reported to protect any innocent parties involved to avoid injuries or even fatality

• Mar 23, 2023GA
  Electrical system

  There was an instance a couple months ago where I was driving and my ignition stopped. To my luck, I was in a safe area to stop but it is dangerous for this to be happening with my car while I am driving.

• Mar 7, 2023IL
  Electrical system · Power train · Steering
  UNKNOWN -- During driving the vehicle the radio and power steering will stop working, locks and key for occasionally have issues, and the car shuts down and has to be re-started. Sometimes will take a minute or two to be able to be re-started. If car stalls at high speeds could cause a…

  UNKNOWN -- During driving the vehicle the radio and power steering will stop working, locks and key for occasionally have issues, and the car shuts down and has to be re-started. Sometimes will take a minute or two to be able to be re-started. If car stalls at high speeds could cause a catastrophic accident, injuring possibly killing driver or other drivers due to not being able to control the car. Car has recently been serviced replacing the radiator, coolant tank, and purge valve (this was throwing the check engine light). No codes can be found and the problem cannot be duplicated. Happens at random times, nothing triggers it.

• Jun 28, 2021OH5,000 mi
  Air bags
  The contact owns a 2020 Chevrolet Sonic. The contact stated that while her granddaughter was driving approximately 40 mph, the front driver’s and passenger’s side air bags erroneously deployed causing the driver to lose control of the steering wheel and the vehicle drove off the roadway. The…

  The contact owns a 2020 Chevrolet Sonic. The contact stated that while her granddaughter was driving approximately 40 mph, the front driver’s and passenger’s side air bags erroneously deployed causing the driver to lose control of the steering wheel and the vehicle drove off the roadway. The vehicle was not involved in a crash before the air bags deployed. The cause of the failure was not yet determined. The local dealer was contacted and informed of the failure. The manufacturer was not notified of the failure. The approximate failure mileage was 5,000.

• Oct 26, 2020FL1,800 mi
  Electrical system · Power train
  Manufacturers owners manual instructions may lead to transmission / electrical failures which may cause an accident when traveling. the recreational towing instructions require that fuses be removed (step 5) before next steps including shifting vehicle into park and turning ignition to the on…

  Manufacturers owners manual instructions may lead to transmission / electrical failures which may cause an accident when traveling. the recreational towing instructions require that fuses be removed (step 5) before next steps including shifting vehicle into park and turning ignition to the on position . those steps ( 6-9) can not be executed if step 5 IS executed first. owners who attempt to prepare the vehicle for recreational towing by using a different sequence run the risk of damaging their vehicles and/or causing severe accidents if the transmission locks up under tow (moving). dealer claims IS vin specific. it IS not vin specific. I tested several identical vehicles on the dealer lot and they all fail, using the manufacturer instructions.

• Feb 11, 2020IN
  Electrical system › Ignition

  2020 chevrolet sonic. Consumer writes in regards to defective keyless ignition. *Ld the consumer stated the it was possible to turn off the keyless entry without first putting the vehicle in park. It IS also possible to shift out of park before starting the ignition. *Js

Service bulletins

Technical service bulletins and other communications the manufacturer sent dealers about this vehicle. Ask a dealer for the full document by its number.

• 11011996This service bulletin provides diagnostic/repair information to correct a customer concern of Cellphone not Charging or USB Receptacle Inoperative.
• 11011989This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.
• 11011900This diagnostic tip bulletin provides additional information on how to diagnose a possible valve, lifter or camshaft issue.
• 11011805This Preliminary information communicates a GM part number forreflective high temperature heat or insulating tape when repairing wiring harnesses.
• 11011782This Preliminary Information communication provides information to the technician about the use of J-35616-64B terminal test probe, replacement terminals, and terminated leads. The J-35616-64B is the latest test probe released for checking tension or probing the .64 series terminals. The test probe terminal has been released in the terminal repair kit (J-38125-620H) located in Lear Tray 7 part number 963716-2. There are 5 terminated leads in a package part number is 13505346, which can be ordered through your normal General Motors Customer Care and Aftersales parts channel.
• 11011709This bulletin advises the dealers to maintain the vehicle stock on hand by doing a full inspection on the vehicles before being sold (prepping) to the customer.
• 11011444This Preliminary information communicates to the dealer a process for accessing the procedure to add attachments to a GM technical assistance case using the dealer case management tool.
• 11011420This Preliminary information communicates to the dealer technician that TAC recommends the utilization of the GDS2 software to aid in diagnosing automatic transmission concerns. TAC is requesting the GDS2 session logs be sent in before the dealer contacts TAC.
• 11011205This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
• 11011119This Preliminary information communicates to dealers GM is working on a solution for outdated Apps
• 11010651This service bulletin informs the technician of an alternate lift procedure that has been developed when the lift plate does not fit the top of the transmission case for 6T30, 6T35, 6T40, 6T45, and 6T50 Transmissions.
• 11010576This service bulletin provides information on All hazmat parts being returned to the Warranty Parts Center (WPC) must be shipped using Central Transport. Hazardous materials should never be sent by air transportation to the WPC.
• 11010545This service bulletin provides information on key code security rules and information on GM keycode look-up applications (U.S).
• 11010495This bulletin provides information on Warranty Administration Required Operating Procedures - 8 Points (U.S. Only).
• 11010493This warranty administration service bulletin provides information about GM Accessories - Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.
• 11010491This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
• 11010490This service bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
• 11010488This Warranty Administration bulletin provides information on the Global Warranty Management (GWM) Warranty Parts Center (WPC) Parts Return Program.
• 11010421This warranty administration bulletin provides policy information on the requirements for 12V battery testing and warranty replacements.
• 11009764This service bulletin provides information on Concerns or Questions Regarding Installation of Dealer Installed Accessories.
• 11009760This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during transit and or long period of stand time at the dealerships.
• 11009756This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
• 11009532This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
• 11009531This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
• 11009170This Preliminary information communicates additional information on how a LIN bus operates and diagnostic tips when working on a LIN bus.
• 11009156This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8 starting/charging tester and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.
• 11009088This service bulletin provides information on some vehicles that may rock or move slightly forward or rearward while in Park at start up after cold soak. This condition may be accompanied by a clunk noise. This is a slight movement that is more often seen visually, rather than felt, when viewed from the outside and using the auto-start feature, if equipped.
• 11009039This warranty administration bulletin provides policy information, proper labor operation selection and causal part identification for warranty transactions (U.S. Only).
• 11009037This service bulletin provides information on Enhancing Field Product Reports with Digital Pictures.
• 11008986This Preliminary information communicatesdirection and examples when diagnosing multiple DTCs, one of which includes U**** Byte 71 DTC.
• 11008956This service bulletin provides information for dealers/technicians on When and How to Submit a Field Product Report (FPR) (U.S. and Canada Dealers Only).
• 11008906This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement.
• 11008898The bulletin provides direction on how to locate the Temporary Service Part (TSP) form in GlobalConnect.
• 11007936This service bulletin provides information to dealership personnel on diagnosis and replacement of shock absorber and strut due to fluid leak.
• 11007935This service bulletin provides information to dealership personnel on diagnosis and replacement of shock absorber and strut due to fluid leak.
• 11007777This Preliminary information communicates that the radio remaining on for 11 minutes after RAP is canceled willresolve itself after a few drive cycles.
• 11007744This Preliminary Information communication provides information to the technician about vehicles that the Heater-Vent-Air Conditioning blows warm air. Before calling General Motors Technical Assistance Center technician will need to have high and low pressures, outside temperature, humidity, and vent temperature.
• 11007743This Preliminary Information communication provides information to the technician about vehicles that the Heater-Vent-Air Conditioning blows warm air. Before calling General Motors Technical Assistance Center technician will need to have high and low pressures, outside temperature, humidity, and vent temperature.
• 11007721This service bulletin provides information on AGM batteries that require less frequent charging in storage.
• 11007208This Preliminary Information communication provides information to the technician about changing the tire and wheel size on vehicles. General Motors will only support a tire calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. Technician should not use the information that is provided by the antilock braking system tire size selection.

Every Chevrolet Sonic model year

Bars are owner complaints, dots mark years with recalls. Select a year to open its report.