C1391 on the 2012 Toyota Prius C
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
This code is specific to a manufacturer and is not described here. Its meaning is in the manufacturer's service information.
| T-SB-0028-21 | 2021-06-21. Service bulletin. TSB: Some 2012 ? 2014 model year Prius C hybrid vehicles may exhibit a condition in which the brake, ABS, and/or TRAC warning lights are on and/or a Check VSC message displays. Diagnostic Trouble Codes (DTCs) C1391, C1252, C1256, and/or C1253 may also be stored. This condition may be caused by a small internal brake fluid leak inside the brake booster assembly with master cylinder. Follow the Repair Procedure in this bulletin to address this condition. |
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1 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.