P12A6 on GMC vehicles
P12A6 is named on 24 GMC model years (2017–2024): 201 manufacturer filings and 1 owner report in NHTSA’s files, across Yukon, Terrain, Sierra, Sierra 2500HD, Sierra 3500HD and 2 more.
Which GMC model years name P12A6
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2021 GMC Yukon | Engine | 22 | — |
| 2020 GMC Terrain | Engine | 20 | — |
| 2020 GMC Sierra | Engine | 18 | — |
| 2020 GMC Sierra 2500HD | Engine | 18 | — |
| 2021 GMC Terrain | Engine | 16 | — |
| 2020 GMC Yukon | Engine | 16 | — |
| 2019 GMC Sierra | Engine | 15 | — |
| 2021 GMC Sierra | Engine | 14 | — |
| 2021 GMC Sierra 2500HD | Engine | 14 | — |
| 2020 GMC Sierra 3500HD | Engine | 11 | 1 |
| 2021 GMC Sierra 3500HD | Engine | 7 | — |
| 2022 GMC Terrain | Electrical System | 4 | — |
| 2021 GMC Acadia | Power Train | 3 | — |
| 2019 GMC Sierra 2500HD | Engine | 3 | — |
| 2018 GMC Sierra 2500HD | Engine | 3 | — |
| 2017 GMC Sierra 2500HD | Engine | 3 | — |
| 2023 GMC Sierra 2500HD | Not specified | 2 | — |
| 2023 GMC Sierra 3500HD | Not specified | 2 | — |
| 2022 GMC Sierra 2500HD | Not specified | 2 | — |
| 2022 GMC Sierra 3500HD | Not specified | 2 | — |
| 2019 GMC Sierra 3500HD | Engine | 2 | — |
| 2017 GMC Sierra 3500HD | Engine | 2 | — |
| 2024 GMC Terrain | Electrical System | 1 | — |
| 2021 GMC Savana | 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.
GMC filings that name P12A6
Source: NHTSA manufacturer communicationsBulletins and campaigns GMC filed with NHTSA whose summary names P12A6. Quote the document number at the service desk — it is a diagnosis the maker has already written down.
- PIP5733A Service bulletin2020-07-29 · Electrical System
- This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
- PIP5733B Service bulletin2020-08-06 · Equipment
- This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
- PIP5733C Service bulletin2020-08-27 · Engine
- This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
- PIP5719A Service bulletin2020-04-17 · Engine And Engine Cooling
- This Preliminary information communicates the possibility of dtc P12A6 with the possibility of a crank no start or extended crank concern.
- PIP5719B Service bulletin2020-04-27 · Engine And Engine Cooling
- This Preliminary information communicates the possibility of dtc P12A6 with the possibility of a crank no start or extended crank concern.
- PIP5733 Service bulletin2020-06-11 · Engine
- This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
- PIP5733D Service bulletin2020-09-22 · Engine And Engine Cooling
- This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
- 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.
- 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.
- 20NA218 Service bulletin2021-04-23 · Power Train
- 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 · 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. The record above is what GMC 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 P12A6 a known problem on GMC vehicles?
It is a documented one: NHTSA's files hold 201 manufacturer filings and 1 owner report naming P12A6 on 24 GMC model years (2017–2024). 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 GMC models does P12A6 appear on most?
2021 Yukon (22 documents), 2020 Terrain (20 documents), 2020 Sierra (18 documents).
Does P12A6 on a GMC 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.