DTC C1252: Brake Booster Pump Motor on Time Abnormally Long; DTC C1253: Pump Motor Relay [10/2018 - ]: Description

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The skid control ECU (brake booster with master cylinder assembly) detects decreases in the accumulator pressure according to the data from the accumulator pressure sensor, and then starts and stops the pump motor by operating the motor relay.

DTC No.	Detection Item	INF Code	DTC Detection Condition	Trouble Area	MIL	Note
C1252	Brake Booster Pump Motor on Time Abnormally Long	311	The pump motor is operating continuously for 178 seconds or more. (When the relay is malfunctioning for 98 seconds or more.)	Short in pump motor circuit or pump motor monitor circuit Motor relay stuck Accumulator pressure sensor malfunction Skid control ECU (brake booster with master cylinder assembly)	Comes on	INF Code 311: SAE Code C0594 Electronically controlled brake system DTC
C1253	Pump Motor Relay	321 322 327 328	INF Code: 321, 327, 328 An open is detected in the motor relay drive circuit for 0.2 seconds or more. INF Code: 322 A short is detected in the motor relay drive circuit for 2 seconds or more.	INF Code: 321, 327, 328 Open in pump motor circuit or pump motor monitor circuit Skid control ECU (brake booster with master cylinder assembly) INF Code: 322 Short in pump motor circuit or pump motor monitor circuit Skid control ECU (brake booster with master cylinder assembly)	Comes on (When only SAE code C121D or SAE code C121E is stored)	INF Code 321: SAE Code C121D INF Code 322: SAE Code C121E Electronically controlled brake system DTC