C1231: owner reports and bulletins

Chassis. We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got C1231 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

10 complaints filed with NHTSA mention C1231, across 2 different models. The component owners most often filed it under: electronic stability control (esc).

Most-reported models

VehicleComplaintsModel years reported
TOYOTA SEQUOIA62001, 2003
TOYOTA SEQUOIA SR542003

Manufacturer service bulletins that name C1231

1 technical service bulletins and manufacturer communications filed with NHTSA mention C1231, from 1 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • TOYOTA CAMRY (2009, 2010, 2011), bulletin 10132241: Some 2009 ? 2011 model year North American production (NAP) vehicles equipped with BOSCH made ABS/VSC systems may exhibit a repeated ABS and TRAC Warning Light ?ON? with Diagnostic Trouble Code (DTC) C1231 present. The A…

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.