DTC C1256: Accumulator Low Pressure [06/2018 - ]: Description

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The accumulator pressure sensor is built into the brake actuator (brake booster with master cylinder assembly) and detects the accumulator pressure.

The skid control ECU (brake booster with master cylinder assembly) turns on the brake warning light / red (malfunction) and brake warning light / yellow (minor malfunction), and sounds the meter buzzer if it senses a decrease in the accumulator pressure.

DTC C1256 may be stored if the accumulator pressure drops due to frequent braking (this is not a malfunction).

DTC No.	Detection Item	INF Code	DTC Detection Condition	Trouble Area	MIL	Note
C1256	Accumulator Low Pressure	341 1125	Significant drop in accumulator pressure continues. (DTCs will be stored and the buzzer will operate when either condition is met.)	Accumulator pressure dropped due to frequent brake pedal operation (not a malfunction) Pump motor malfunction Accumulator deterioration Accumulator pressure sensor (brake booster with master cylinder assembly) Supply voltage reduced	Comes on (When only SAE code C1256 is stored)	INF Code 341: SAE Code C1256 Electronically controlled brake system DTC