According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2020 Chevrolet Onix has 4 documented known issues, with 2 rated critical. The most serious are Engine Fire Risk from ECM Calibration Defect — 1.0 Turbo (Brazil Recall) ($0-$0 repair) and Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime) ($300-$2,500 repair). Across all issues with published estimates, repair costs range from $60 to $2,500. DIY maintenance guides at au7o.io.
On the 2020 Chevrolet Onix, shortly after the second-generation Onix launched in Brazil, GM recalled 19,055 Onix Plus model-year 2020 sedans (produced April 29 to November 6, 2019, chassis LG100091-LG139164) because a faulty engine control module calibration on the new 1.0 turbo three-cylinder could cause abnormal pressure and temperature in the combustion chamber under certain conditions of atmospheric pressure, humidity and fuel composition. The resulting pre-ignition could break pistons, connecting rods or even the engine block, letting hot oil spray onto exhaust components and ignite. At least one vehicle fire was reported in Brazil's Northeast and another occurred at the Gravataí factory, and videos of burning units pressured Procon-SP to notify GM before the recall was formalized in November 2019. Some owners subsequently reported reduced power after the recalibration.
Common Symptoms
Sudden loss of power while driving
Loud knocking or metallic banging from the engine
Oil leaking under the engine bay
Smoke or flames from the engine compartment
Check engine light after hard acceleration
How to Fix
Free ECM software recalibration at any Chevrolet Brazil dealership (recall service started November 18, 2019; GM offered loaner cars during repairs). Check recall completion on any used MY2020 Onix Plus/Onix 1.0 turbo via the Chevrolet Brasil recall portal using the chassis number. If the engine already suffered piston or block damage, GM replaced engine components under the campaign/warranty.
On the 2020-2024 Chevrolet Onix, the second-generation Onix and Onix Plus 1.0 turbo (CSS Prime three-cylinder, introduced 2019 for MY2020) use a timing belt that runs immersed in engine oil. GM rates the belt for 240,000 km or 15 years, but Brazilian owners, mechanics and the automotive press have documented widespread premature degradation and outright belt failures between roughly 50,000 and 100,000 km — sometimes under 50,000 km. Oil that does not meet the required Dexos specification (0W-20 for naturally aspirated, 5W-30 for turbo), extended oil-change intervals, sludge or contaminated fuel attacks the belt rubber, which dries, sheds teeth and disintegrates; debris can also clog the oil pickup. When the belt snaps on this interference engine, pistons strike valves and the repair can involve a full cylinder head rebuild or engine replacement, easily exceeding R$10,000. The problem became serious enough that GM South America announced a service action to inspect and replace belts on affected Onix, Onix Plus, Tracker and Montana units, while many warranty claims were initially denied over oil-spec documentation.
Common Symptoms
Ticking or rattling noise from the timing cover area
Rubber debris or dark sludge found in the engine oil
Check engine light with cam/crank correlation faults
Engine cranks but will not start after belt failure
Sudden engine stop with loss of power steering assist
How to Fix
Use only Dexos-certified oil of the exact specification (5W-30 Dexos 1 for the turbo) and change it strictly on schedule at shorter real-world intervals. Independent Brazilian mechanics recommend preventive belt replacement around 60,000-70,000 km instead of the 240,000 km book interval. Have the belt inspected for swelling, cracking or tooth loss at every oil change; if debris is found in the oil, replace the belt and clean the oil pickup. Vehicles with documented dealer maintenance can claim the GM verification/replacement campaign or warranty coverage.
On the 2020-2024 Chevrolet Onix, a chronic and widely reported air-conditioning fault affects second-generation Onix and Onix Plus models (2020+), with similar AC complaints also common on the first generation. The system cools normally for the first few minutes after start-up, then begins blowing warm air even though the compressor stays engaged and refrigerant pressure reads normal; cooling temporarily returns after the car is shut off and restarted. Brazilian AC specialists traced the recurring fault to the expansion valve jamming, which drastically reduces suction in the circuit. Because gauge pressures look normal, shops frequently misdiagnose the problem and replace the compressor (around R$2,000) without fixing anything. The original valve design is considered flawed, so replacement with the same OEM part can fail again; some specialists fit an alternative valve for durability. Complaints about the Onix AC blowing hot air and 'vinegar smell' from the vents are among the most common entries for the model on Reclame Aqui and the Opinautos defect database.
Common Symptoms
AC cools at first, then blows warm air after a few minutes
Compressor stays engaged but no cold air comes out
Cooling returns temporarily after turning the car off and on
Sour or vinegar-like smell from the vents
Weak airflow from dash vents in hot weather
How to Fix
Replace the AC expansion valve (part approximately R$300) rather than the compressor — confirm the diagnosis by checking evaporator suction behavior, not just static pressures. Replace the cabin filter and sanitize the evaporator if there is a sour smell. Under factory warranty, Chevrolet dealers replace the valve free of charge; out of warranty, some specialists install a more durable alternative valve to prevent recurrence.
On the 2020-2023 Chevrolet Onix, owners of 2020-2023 Onix and Onix Plus report recurring failures of the MyLink infotainment system: the screen freezes on the boot logo or with a frozen image, flickers or goes black, the touchscreen and hard buttons stop responding, and the unit reboots randomly. A separate but related software defect causes wireless Android Auto to disconnect intermittently with a 'Wi-Fi interference' message. Because the reversing camera displays through the head unit, a frozen or black screen also takes out the camera image. Complaints are concentrated on Reclame Aqui and the Clube do Onix owner forum across MY2020-2023 vehicles, and GM's fix is a software update applied via official USB pendrive at dealerships — some out-of-warranty owners report being charged for the update, which itself generated complaints.
Common Symptoms
Screen frozen on the MyLink boot logo
Touchscreen and buttons stop responding
Screen flickers, blinks or goes black while driving
Wireless Android Auto disconnects with Wi-Fi interference message
Reverse camera image unavailable when screen freezes
System reboots by itself
How to Fix
Have the dealer apply the latest MyLink firmware update (official GM pendrive procedure) — free under warranty. A temporary workaround for a frozen screen is a system reboot (hold the power button, or lock/unlock the car and let it sleep). For wireless Android Auto dropouts, updating both the head unit firmware and using a quality USB cable connection avoids the Wi-Fi interference bug. Persistent hardware-level failures require head unit replacement under warranty.
According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2020 Chevrolet Onix has 4 documented issues. The most frequently reported are: Engine Fire Risk from ECM Calibration Defect — 1.0 Turbo (Brazil Recall), Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime), Air Conditioning Stops Cooling — Expansion Valve Jamming. Of these, 2 are rated critical and should be addressed promptly.
Is the Chevrolet Onix reliable?
The 2020 Chevrolet Onix has 4 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 2 issues are rated critical: Engine Fire Risk from ECM Calibration Defect — 1.0 Turbo (Brazil Recall) and Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime). Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Chevrolet Onix problems?
Repair costs for known Chevrolet Onix issues range from $0 to $2,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Engine Fire Risk from ECM Calibration Defect — 1.0 Turbo (Brazil Recall), typically costs $0-$0 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2020 Chevrolet Onix Engine Fire Risk from ECM Calibration Defect — 1.0 Turbo (Brazil Recall)?
Shortly after the second-generation Onix launched in Brazil, GM recalled 19,055 Onix Plus model-year 2020 sedans (produced April 29 to November 6, 2019, chassis LG100091-LG139164) because a faulty engine control module calibration on the new 1.0 turbo three-cylinder could cause a… Repairs typically run $0-$0. Severity: high.
What is the 2020-2024 Chevrolet Onix Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime)?
The second-generation Onix and Onix Plus 1.0 turbo (CSS Prime three-cylinder, introduced 2019 for MY2020) use a timing belt that runs immersed in engine oil. GM rates the belt for 240,000 km or 15 years, but Brazilian owners, mechanics and the automotive press have documented wid… Repairs typically run $300-$2,500. Severity: high.
What is the 2020-2024 Chevrolet Onix Air Conditioning Stops Cooling — Expansion Valve Jamming?
A chronic and widely reported air-conditioning fault affects second-generation Onix and Onix Plus models (2020+), with similar AC complaints also common on the first generation. The system cools normally for the first few minutes after start-up, then begins blowing warm air even… Repairs typically run $60-$450. Severity: medium.
What is the 2020-2023 Chevrolet Onix MyLink Infotainment Freezing, Black Screen and Wireless Android Auto Dropouts?
Owners of 2020-2023 Onix and Onix Plus report recurring failures of the MyLink infotainment system: the screen freezes on the boot logo or with a frozen image, flickers or goes black, the touchscreen and hard buttons stop responding, and the unit reboots randomly. A separate but… Repairs typically run $0-$150. Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.
