DTC C1256/57 Accumulator Low Pressure: Description

The accumulator pressure sensor is built into the actuator and detects the accumulator pressure.

The skid control ECU turns on the brake warning light / yellow (minor malfunction) and sounds the skid control buzzer if it senses a decrease in the accumulator pressure.

HINT:

DTCs may be output if the accumulator pressure drops due to frequent braking (this is not a malfunction).

DTC DETECTION CONDITION CHART

DTC Code	Information Code	DTC Detection Condition	Trouble Area
C1256/57	141	When either of the following is detected (after a condition is met, the code is stored and the buzzer sounds): When inputting the vehicle speed, the brake operation is input with the accumulator pressure low or the accumulator pressure extremely decreases while braking for 0.3 seconds or more. The accumulator pressure has been low since system start and the pressure is less than 14.62 MPa for 120 seconds.	Brake accumulator pump Skid control ECU
↑	143	When any of the following is detected: When inputting the vehicle speed, any of the wheel cylinder pressure sensor values is lower than the specified value with the accumulator pressure low for 0.5 seconds or more. The accumulator pressure decreases without increasing the wheel cylinder pressure of each wheel. With the motor relay abnormal or off, the accumulator pressure is less than 14.62 MPa for 0.5 seconds or more.	↑