C1256 code in owner complaints

Code C1256 is named in 71 US owner complaints, 1 of them (1%) after a crash. Models: 15, model years 1999–2018.

There is little data for this code or its meaning is ambiguous, so this page is not indexed.

What the code means

This is a manufacturer-specific code: the meaning depends on the make and sometimes on the year.

How to read C1256: the letter C means chassis (brakes, ABS, steering, suspension); the second digit 1 marks a manufacturer code whose meaning is set by the make; the last three characters 256 identify the specific fault.

ABS/ESC codes: wheel speed sensors, the ABS hydraulic unit and pump, brake booster, pressure and yaw sensors. A hit to a wheel or suspension often damages the wheel speed sensor or its wiring, so on a damaged car this code is a reason to inspect the hub, knuckle and control arms, not just swap the sensor.

Key figures

Complaints with this code: 71
after a crash: 1 (1%)
Models: 15
Model years: 1999–2018

Which models and years

Models whose owners name this code (15). Years link to the model year problems page.

Model	Years	Complaints
Toyota Prius	2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013, 2014, 2015	34
Toyota Highlander Hybrid	2006, 2007, 2008, 2012	7
Lexus CT	2013, 2014, 2015	6
Toyota Highlander	2006, 2008, 2018	5
Toyota Prius V	2012, 2013	5
Lexus HS	2010	2
Lexus RX	2008, 2011	2
Toyota 4runner	2004	2
Toyota Prius C	2012, 2013	2
Ford Windstar	1999	1
Lexus LS	2013	1
Lexus RX Hybrid	2006	1
Toyota Avalon Hybrid	2015	1
Toyota Camry	2009	1
Toyota Land Cruiser	2005	1

Components named together with the code

Component as the owner filed it (one complaint can list several).

Service brakes 71
Electrical system 9
Electronic stability control 6
Forward collision avoidance 4
Other 4
Vehicle speed control 2
Fuel/propulsion system 1
Fuel system 1

Complaints by model year

1999 1
2004 5
2005 2
2006 6
2007 2
2008 14
2009 4
2010 6
2011 1
2012 9
2013 13
2014 4
2015 3
2018 1

What to do if an auction car has this code

Inspect the wheel and suspension on the impact side: the wheel speed sensor is often damaged together with the hub or knuckle.
Check whether the ABS and ESC lights stay on after start-up.
After replacing sensors or the hydraulic unit, bleeding and scan tool adaptation may be required.

What owners report

Excerpts of owner complaints in the original wording. Owner statements not verified by the regulator; personal data removed.

8.) drove 4runner approximately 10-11 miles, hit brakes, brakes failed, abs and brake light on, warning/buzzer sound, crash - no fatalities. 9.) codes from dealer C1223, C1251, C1256; brake fluid level good. 10.) dealer replaced abs and master cylinder. $3,356 repair cost.
Toyota 4runner 2004 · 2014-05 · crash
The vehicle was not driven after the failure and was transported to a Toyota dealership for diagnosis. The dealer confirmed a brake-system fault and recorded diagnostic trouble codes C1241, C1252, C1253, and C1256.
Toyota Prius 2013 · 2026-10
This happened more than once while driving and I almost crashed because I couldn't stop the car in time. A scan later showed codes C1252 (brake booster pump motor on-time abnormally long), C1253 (pump motor relay fault), and C1256 (accumulator pressure low), pointing to a failure in the brake booster pump/accumulator…
Toyota Prius 2013 · 2026-10

Related codes

Sources: public official US data (owner complaints) and the SAE J2012 standard. Complaints are owner statements not verified by the regulator. A code from a complaint does not replace a scan tool diagnosis. Data updated 2026-11-10.