U1601 on Ram vehicles
U1601 is named on 12 Ram model years (2019–2024): 34 manufacturer filings and 0 owner reports in NHTSA’s files, across 2500, 3500.
Which Ram model years name U1601
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2020 Ram 3500 | Engine | 5 | — |
| 2019 Ram 2500 | Electrical System | 5 | — |
| 2019 Ram 3500 | Engine | 5 | — |
| 2021 Ram 3500 | Electrical System | 4 | — |
| 2020 Ram 2500 | Engine | 4 | — |
| 2021 Ram 2500 | Electrical System | 3 | — |
| 2022 Ram 2500 | Engine | 2 | — |
| 2022 Ram 3500 | Engine | 2 | — |
| 2024 Ram 2500 | Engine | 1 | — |
| 2024 Ram 3500 | Engine | 1 | — |
| 2023 Ram 2500 | Engine | 1 | — |
| 2023 Ram 3500 | Engine | 1 | — |
A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.
Ram filings that name U1601
Source: NHTSA manufacturer communicationsBulletins and campaigns Ram filed with NHTSA whose summary names U1601. Quote the document number at the service desk — it is a diagnosis the maker has already written down.
- S2008000186 Service bulletin2020-11-20 · Electrical System
- Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 ? ECU Application Software Code 1 Missing Or Corrupted
- S2008000186 Service bulletin2020-11-20 · Electrical System
- Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 ? ECU Application Software Code 1 Missing Or Corrupted
- S2008000186 Service bulletin2020-11-20 · Electrical System
- Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 ? ECU Application Software Code 1 Missing Or Corrupted
- S2008000186REVA Service bulletin2022-08-15 · Engine And Engine Cooling — Engine — Engine Control Module (Ecu/Ecm)
- Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 ? ECU Application Software Code 1 Missing Or Corrupted
- S2008000186 REV. B Service bulletin2024-12-19 · Engine
- Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 – ECU Application Software Code 1 Missing Or Corrupted
What U1601 means
Source: SAE J2012 / OBD-IIU1601 is a manufacturer-specific code: the second character is a 1, which under the OBD-II standard hands the definition to whoever built the vehicle. The same code can mean one thing on a Ford and something unrelated on a Hyundai. Any site that prints a single definition for it is guessing.
A stored code names the test that failed, never the part that caused it. The record above is what Ram and its owners have filed about it; the code’s page across every make has the whole file.
Common questions
Source: NHTSA files and the OBD-II standardIs U1601 a known problem on Ram vehicles?
It is a documented one: NHTSA's files hold 34 manufacturer filings and 0 owner reports naming U1601 on 12 Ram model years (2019–2024). Whether it is a problem on one particular car is a diagnosis, not a count — but a bulletin that names the code on your model year is the place to start.
Which Ram models does U1601 appear on most?
2019 2500 (5 documents), 2020 3500 (5 documents), 2019 3500 (5 documents).
Does U1601 on a Ram mean it is recalled?
No. Recalls are filed by campaign and matched by VIN; no recall is triggered by a scan tool. Check the VIN at nhtsa.gov/recalls, or open the model year's page here for the campaigns filed against it.