U029D: owner reports and bulletins
Got U029D 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
5 complaints filed with NHTSA mention U029D, 5 of them since 2015, across 3 different models. The component owners most often filed it under: electrical system.
Most-reported models
| Vehicle | Complaints | Model years reported |
|---|---|---|
| CHEVROLET SILVERADO 2500 | 3 | 2014, 2017, 2022 |
Manufacturer service bulletins that name U029D
18 technical service bulletins and manufacturer communications filed with NHTSA mention U029D, from 7 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:
- MACK MID-LINER (1983, 1984, 1985, 1990), bulletin 10213633: USE FOR NEW VEHICLES (US21+OBD22 Emissions) - Intermittent Diagnostic Trouble Codes U02A3, U029D, U029E
- MACK ANTHEM (AN) (2021, 2022, 2023), bulletin 10219423: USE FOR NEW VEHICLES (US21+OBD22 Emissions) - Intermittent Diagnostic Trouble Codes U02A3, U029D, U029E
- FORD F-600 SD (2023), bulletin 10238282: Some 2023 F-Super Duty vehicles equipped with a 6.7L engine, and built on or before 02-May-2023, may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) U029D, U029E, U02A1, U02A3,…
- FORD F-550 SD (2023), bulletin 10239482: Some 2023 F-Super Duty vehicles equipped with a 6.7L engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) U029D, U029E, U02A1, U02A3, P2209, P24D0, P22A7, and/or P23B5. T…
- VOLVO VNX (2021, 2022, 2023), bulletin 10241907: CBR: Intermittent Diagnostic Trouble Codes U02A3,U029D, U029E - USE FOR NEW VEHICLES (US21+OBD22 Emissions)
- MACK GRANITE (GU) (2021, 2022, 2023), bulletin 10241914: CBR: Intermittent Diagnostic Trouble Codes U02A3,U029D, U029E - USE FOR NEW VEHICLES (US21+OBD22 Emissions)
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.