P0023: owner reports and bulletins

Powertrain (generic, all makes). We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got P0023 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.

What owners report to NHTSA

No consumer complaints filed with NHTSA mention P0023. That usually means it's rare, or owners don't quote the code when they file.

Manufacturer service bulletins that name P0023

7 technical service bulletins and manufacturer communications filed with NHTSA mention P0023, from 5 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • SUBARU FORESTER (2023), bulletin 10244897: This bulletin announces availability of reprogramming files for the Engine Control Module (ECM) to address rare cases of DTCs P0011 (A Camshaft Position Timing Over-Advanced or System Performance Bank 1) and P0021 (A Cam…
  • DODGE CHALLENGER (2023), bulletin 10248935: Cam Phaser Actuators Replacement Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation, the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) …
  • CHRYSLER 300 (2023), bulletin 10248935: Cam Phaser Actuators Replacement Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation, the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) …
  • JEEP GLADIATOR (2021), bulletin 10221660: 3.6L Check Engine Light and Rough Running Engine This bulletin involves cutting off a wiring harness eyelet and splicing in a pigtail to the engine ground harness. Customers may experience a Malfunction Indicator Lamp (M…
  • RAM 1500 (2021), bulletin 10221658: 3.6L Check Engine Light and Rough Running Engine This bulletin involves cutting off a wiring harness eyelet and splicing in a pigtail to the engine ground harness. Customers may experience a Malfunction Indicator Lamp (M…

Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.