P10D9
2 owner reports and 12 manufacturer filings across 6 model years from Chevrolet, GMC.
Where P10D9 shows up
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2021 Chevrolet Silverado 2500HD | Electrical System | 2 | 1 |
| 2020 Chevrolet Silverado 3500HD | Electrical System | 2 | 1 |
| 2021 Chevrolet Silverado 3500HD | Electrical System | 2 | — |
| 2021 GMC Sierra 2500HD | Fuel System, Diesel | 2 | — |
| 2021 GMC Sierra 3500HD | Electrical System | 2 | — |
| 2020 GMC Sierra 3500HD | Electrical System | 2 | — |
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.
What it gets filed under
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names P10D9. Quoting the document number at a service desk is often the fastest route to a diagnosis someone has already written down.
- N212342980-012022-02-04 · Fuel System, Diesel
- Service Update. On certain vehicles equipped with a 6.6L diesel engine (RPO L5P), the DEF tank connector may overheat and set the following diagnostic codes (P10D9, P143C and P10F3), which will result in reduced engine speed. Dealers are to reprogram the reductant control module.
- N2123429802022-01-20 · Electrical System
- On certain vehicles equipped with a 6.6L diesel engine (RPO L5P), the DEF tank connector may overheat and set the following diagnostic codes (P10D9, P143C and P10F3), which will result in reduced engine speed. Dealers are to reprogram the reductant control module.
What P10D9 means
Source: SAE J2012 / OBD-IIP10D9 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. 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 P10D9
Source: NHTSA files and the OBD-II standardWhy does this page not define P10D9?
Because it cannot be defined honestly. The second character of a trouble code says who owns its meaning, and a 1 or a 3 hands that to the manufacturer. Sites that print one definition for a manufacturer-specific code are showing you one automaker's meaning and hoping it is yours.
Can I keep driving with P10D9 stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light generally means the fault was logged and the vehicle is in a reduced-risk mode; a flashing light means stop soon, because a misfiring engine can destroy a catalytic converter in minutes. 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.