P203B
2 owner reports and 99 manufacturer filings across 32 model years from Chevrolet, Ford, Jaguar, Ram.
Where P203B shows up
Source: NHTSA manufacturer communications and complaintsShowing the 25 model years where P203B appears most; it is on file for 32 in total.
A model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.
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P203B by make
The same record, one make at a time: the model years, bulletins and owner reports that name P203B on that maker’s vehicles.
What it gets filed under
What owners said
Source: NHTSA complaint databaseOwners’ own words, one per nameplate, scrubbed of anything identifying. These are unverified reports filed with NHTSA — they are what was said, not a finding that it was true.
The contact stated while driving at approximately 35 MPH, DTC: P203B was displayed on the instrument panel
The code is “DTC P203B”, sometimes indicated as P203B00 is an OBD diagnostic trouble code indicating a manufacturer-specific fault with the vehicle powertrain (i.e
99 manufacturer filings name P203B. Start with what the maker wrote down.
A code names the test that failed, not the part. A bulletin that names it is often a diagnosis someone has already written down — quote its number at the service desk.
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names P203B.
- TSB 24-2256 Service bulletin2024-08-22 · Power Train
- Some 2023-2024 F-Super Duty vehicles built on or before 22-Jul-2024 and equipped with a 6.7L engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) P203B, P206B, and/or P2201:92 stored in the powertrain control module (PCM). This may be due to the software in the PCM. To correct the condition, follow the Service Procedure to reprogram the PCM using t
- SSM 52299 Service bulletin2024-02-27 · Electrical System
- Some 2023-2024 F-Super Duty vehicles equipped with a 6.7L engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) U02A2, P206B, P203B, P208A, P20FA, P20FD, and/or P20FC stored in the powertrain control module (PCM). Before performing normal diagnostics, inspect connectors C1273C (32 pin) and C406 (14 pin) for proper connection. Also disconnect and ins
- SSM 51891 Service bulletin2023-08-28 · Electrical System
- 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) U02A2, P206B, P203B, P208A, P20FA, P20FD, and/or P20FC stored in the powertrain control module (PCM). Before performing normal diagnostics, inspect connectors C1273C (32 pin) and C406 (14 pin) for proper connection. Also disconnect and inspect
- TSB 23-2161 Service bulletin2023-05-23 · Electrical System
- Some 2018-2021 F-150 vehicles equipped with a 3.0L diesel engine, 2016-2022 F-650/F-750 vehicles equipped with a 6.7L engine, and 2017-2022 F-Super Duty vehicles equipped with a 6.7L engine and built on or before 08-Mar-2022 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTCs) P21DD, P20BA. P20B9, P204C, P208A, P208B, P208C, P203B, P205B, P21CD and/or U0
- TSB 22-2191 Service bulletin2022-05-17 · Electrical System
- Some 2018-2021 F-150 vehicles equipped with a 3.0L diesel engine, 2016-2022 F-650/F-750 vehicles equipped with a 6.7L engine, and 2017-2022 F-Super Duty vehicles equipped with a 6.7L engine and built on or before 08-Mar-2022 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTCs) P21DD, P20BA. P20B9, P204C, P208A, P208B, P208C, P203B, P205B, P21CD and/or U0
- TSB 21-2336 Service bulletin2021-09-28 · Electrical System
- Some 2018-2020 F-150 vehicles built on or before 1-Apr-2020 equipped with a 3.0L diesel engine, 2017-2019 F-Super Duty vehicles built on or before 30-Oct-2019 equipped with a 6.7L engine and 2016-2019 F-650/F-750 vehicles built on or before 30-Oct-2019 equipped with a 6.7L engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTCs) P21DD, P20BA. P20B9, P
What P203B means
Source: SAE J2012 / OBD-IIP203B 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. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.
Common questions about P203B
Source: NHTSA files and the OBD-II standardCan I keep driving with P203B stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light means a fault was logged and the car should be checked soon; a flashing light means a severe misfire — slow down and get it seen as soon as possible, because severe misfire can quickly damage the catalytic converter. The safe read of this page is the mileage and the components, not permission.
Does a code mean the car is recalled?
No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.
Why do the counts here differ from other sites?
Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.
Will clearing the code fix it?
Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.