There are 2 owner-reported powertrain & transmission complaints for the 2020 Chevrolet Sonicin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
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
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.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026