P203F on Ram vehicles
P203F is named on 13 Ram model years (2018–2026): 30 manufacturer filings and 1 owner report in NHTSA’s files, across 2500, 3500.
Which Ram model years name P203F
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2025 Ram 2500 | Not specified | 3 | — |
| 2025 Ram 3500 | Not specified | 3 | — |
| 2021 Ram 2500 | Back Over Prevention | 3 | — |
| 2021 Ram 3500 | Fuel/Propulsion System | 3 | — |
| 2020 Ram 2500 | Fuel/Propulsion System | 3 | — |
| 2020 Ram 3500 | Fuel/Propulsion System | 3 | — |
| 2019 Ram 2500 | Back Over Prevention | 3 | — |
| 2019 Ram 3500 | Back Over Prevention | 3 | — |
| 2026 Ram 2500 | Fuel/Propulsion System | 2 | — |
| 2026 Ram 3500 | Fuel/Propulsion System | 2 | — |
| 2022 Ram 2500 | Fuel/Propulsion System | 1 | — |
| 2022 Ram 3500 | Fuel/Propulsion System | 1 | — |
| 2018 Ram 3500 | Service Brakes | — | 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.
What Ram owners said
Source: NHTSA complaint databaseOwners’ own words, scrubbed of anything identifying. Unverified reports filed with NHTSA — what was said, not a finding that it was true.
ABS and Traction Control lights on, beeping, Check Engine Light On, Codes U1408-00, C0020-01, C0044-28, P203F
Ram filings that name P203F
Source: NHTSA manufacturer communicationsBulletins and campaigns Ram filed with NHTSA whose summary names P203F. Quote the document number at the service desk — it is a diagnosis the maker has already written down.
- S2525000002 Service bulletin2025-05-16 · Unknown Or Other
- Diesel Exhaust Fluid (DEF) Gauge Fluctuates Or Is Erratic. Diagnostic Trouble Code (DTC) P203F – Reductant Level Too Low.
- S2525000002 REV. A Service bulletin2026-02-09 · Fuel/Propulsion System
- Diesel Exhaust Fluid (DEF) Gauge Fluctuates Or Is Erratic. Diagnostic Trouble Code (DTC) P203F – Reductant Level Too Low.
- S2525000002 REV. B Service bulletin2026-03-31 · Unknown Or Other
- Diesel Exhaust Fluid (DEF) Gauge Fluctuates Or Is Erratic. Diagnostic Trouble Code (DTC) P203F – Reductant Level Too Low.
- 18-034-21 Service bulletin2021-04-02 · Back Over Prevention
- P203E and P203F Additional Diagnostic Information This bulletin provides additional information regarding diagnosing Diesel Exhaust Fluid (DEF) issue in extreme cold weather. Diagnostic Trouble Codes (DTCs) P203E - Reductant Level Sensor 1 Circuit Intermittent and/or P203F - Reductant Level Too Low set.
- 18-034-21 REV. A Service bulletin2021-11-10 · Back Over Prevention
- P203E and P203F Additional Diagnostic Information This bulletin provides additional information regarding diagnosing Diesel Exhaust Fluid (DEF) issue in extreme cold weather. Diagnostic Trouble Codes (DTCs) P203E - Reductant Level Sensor 1 Circuit Intermittent and/or P203F - Reductant Level Too Low set.
- 1803421 Service bulletin2021-04-02 · Fuel System, Diesel
- P203E and P203F Additional Diagnostic Information This bulletin provides additional information regarding diagnosing Diesel Exhaust Fluid (DEF) issue in extreme cold weather. Diagnostic Trouble Codes (DTCs) P203E - Reductant Level Sensor 1 Circuit Intermittent and/or P203F - Reductant Level Too Low set.
What P203F means
Source: SAE J2012 / OBD-IIP203F sits in the generic range of the OBD-II standard, so it means the same thing on every vehicle sold in the United States — but WhichTrim does not carry a definition for it and will not invent one. What is on this page is the record: who named it and on what.
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 P203F a known problem on Ram vehicles?
It is a documented one: NHTSA's files hold 30 manufacturer filings and 1 owner report naming P203F on 13 Ram model years (2018–2026). 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 P203F appear on most?
2025 2500 (3 documents), 2021 2500 (3 documents), 2020 2500 (3 documents).
Does P203F 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.