P12A6
4 owner reports and 549 manufacturer filings across 62 model years from Buick, Cadillac, Chevrolet, GMC.
Where P12A6 shows up
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports | Parts |
|---|---|---|---|---|
| 2020 Chevrolet Silverado | Engine | 23 | 1 | |
| 2019 Chevrolet Silverado | Engine | 22 | — | |
| 2021 GMC Yukon | Engine | 22 | — | |
| 2021 Cadillac Escalade | Engine | 21 | — | |
| 2020 GMC Terrain | Engine | 20 | — | |
| 2020 Chevrolet Equinox | Engine | 19 | — | |
| 2020 Chevrolet Malibu | Engine | 19 | — | |
| 2020 Chevrolet Silverado 2500HD | Engine | 18 | — | |
| 2020 GMC Sierra | Engine | 18 | — | |
| 2020 GMC Sierra 2500HD | Engine | 18 | — | |
| 2020 Cadillac Escalade | Engine | 16 | — | |
| 2021 Chevrolet Equinox | Engine | 16 | — | |
| 2021 Chevrolet Malibu | Engine | 16 | — | |
| 2020 Chevrolet Suburban | Engine | 16 | — | |
| 2020 Chevrolet Tahoe | Engine | 16 | — | |
| 2021 GMC Terrain | Engine | 16 | — | |
| 2020 GMC Yukon | Engine | 16 | — | |
| 2019 GMC Sierra | Engine | 15 | — | |
| 2021 Chevrolet Silverado | Engine | 14 | — | |
| 2021 Chevrolet Silverado 2500HD | Engine | 14 | — | |
| 2021 GMC Sierra | Engine | 14 | — | |
| 2021 GMC Sierra 2500HD | Engine | 14 | — | |
| 2021 Chevrolet Suburban | Engine | 13 | — | |
| 2021 Chevrolet Tahoe | Engine | 13 | — | |
| 2020 Chevrolet Corvette | Engine | 12 | — |
Showing the 25 model years where P12A6 appears most; it is on file for 62 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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P12A6 by make
The same record, one make at a time: the model years, bulletins and owner reports that name P12A6 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.
Check 4x4, check DEF( def is still at half full), check trailer( no trailer is connected) Took to dealership, 4 active codes P0336, P12A6, U029D, U029E
The engine light has come on 3 times with a truck with only 9000 miles on it I took it to the dealership who gave me a code of P12A6 they told me Chevrolet is aware of this problem but has not come up with solution yet or even wrote a…
549 manufacturer filings name P12A6. 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 P12A6.
- PIT6396A Service bulletin2025-08-05 · Unknown Or Other
- This PI communicates an issue with a SES MIL with DTC P2535, P12A6, P10DA and/or C111B maybe set after replacing the fuel pump driver module. Engineering is working on a fix, but in the meantime, dealers are to install a diode.
- PIT6396 Service bulletin2025-06-11 · Unknown Or Other
- This PI communicates an issue with a SES MIL with DTC P2535, P12A6, P10DA and/or C111B maybe set after replacing the fuel pump driver module. Engineering is working on a fix, but in the meantime, dealers are to install a diode.
- 22-NA-170 Service bulletin2023-09-12 · Electrical System
- This bulletin offers Information on Possible Crank No Start or Extended Crank with DTC P12A6 or Service Safety Restraints message on DIC, with B0073.
- 22-NA-170 Service bulletin2022-09-07 · Electrical System
- This bulletin offers Information on Possible Crank No Start or Extended Crank with DTC P12A6 or Service Safety Restraints message on DIC, with B0073.
- 20-NA-218 Service bulletin2022-05-19 · Engine And Engine Cooling
- This service bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.
- 20NA218 Service bulletin2021-05-07 · Electrical System
- This service bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.
What P12A6 means
Source: SAE J2012 / OBD-IIP12A6 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 P12A6
Source: NHTSA files and the OBD-II standardWhy does this page not define P12A6?
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 P12A6 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.