C0020: owner reports and bulletins
Got C0020 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.
What owners report to NHTSA
299 complaints filed with NHTSA mention C0020, 298 of them since 2015, across 6 different models. The component owners most often filed it under: service brakes.
Most-reported models
| Vehicle | Complaints | Model years reported |
|---|---|---|
| RAM 2500 | 221 | 2013, 2016, 2017, 2018 |
| RAM 3500 | 67 | 2015, 2017, 2018 |
| RAM 1500 | 5 | 2014, 2015, 2017 |
| MAZDA MAZDA3 | 4 | 2010 |
Manufacturer service bulletins that name C0020
17 technical service bulletins and manufacturer communications filed with NHTSA mention C0020, from 4 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:
- FORD F-250 SD (2023, 2024), bulletin 11001366: Some 2023-2024 F-Super Duty vehicles may require a replacement of the anti-lock brake system (ABS) module for various reasons. Replacing the ABS module may result in an error state with diagnostic trouble code (DTC) C002…
- FORD F-550 SD (2020, 2021, 2022), bulletin 10206844: Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the engine will not turn off and/or have various electrical symptoms including a dead battery, horn stays on and no crank/no start. The vehicle may also …
- FORD F-450 SD (2020, 2021, 2022), bulletin 10208141: Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the engine will not turn off and/or have various electrical symptoms including a dead battery, horn stays on and no crank/no start. The vehicle may also …
- FORD F-350 SD (2020, 2021, 2022), bulletin 10226938: This article supersedes TSB 22-2313 to update the Parts List, Service Procedure, and vehicle production fix dates. Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the engine will not turn off and/or ha…
- FORD F-750 SD (2020, 2021, 2022), bulletin 10235151: Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the engine will not turn off and/or have various electrical symptoms including a dead battery, horn stays on and no crank/no start. The vehicle may also …
- FORD EXPLORER POLICE INTERCEPT (2020, 2021), bulletin 10187831: Some 2020-2021 Explorer/Aviator/Police Interceptor Utility vehicles built on or before 24-Dec-2020 may exhibit an illuminated anti-lock brake system (ABS) warning indicator lamp with diagnostic trouble code (DTC) C0020 s…
Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.