ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1257/57

DTC Code DTC Name
C1257/57 Power Supply Drive Circuit

DESCRIPTION

The skid control ECU (brake booster with master cylinder assembly) detects a drop in accumulator pressure according to the signals from the accumulator pressure sensor, then operates and stops the motor relay as well as the pump motor.

The skid control ECU (brake booster with master cylinder assembly) troubleshoots the built-in motor relay drive circuit, and stores this DTC when a malfunction is detected.

DTC No. Detection Item INF Code DTC Detection Condition Trouble Area Note
C1257/57 Power Supply Drive Circuit

361

362

  • INF Code: 361


    • While accumulator pressure falls below hard pump ON pressure, the hard drive circuit does not operate for 1 second or more.


  • INF Code: 362


    • When hard driving, one of the 3 built-in motor relays does not operate for 0.2 seconds or more.

 Skid control ECU (Brake booster with master cylinder assembly) Electronically controlled brake system DTC

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake booster with master cylinder assembly), perform initialization and calibration of the linear solenoid valve.

Click here

Tech Tips

When C1241/41, C1242/42 and/or C1253/53 are output together with C1257/57, inspect and repair the trouble areas indicated by C1241/41, C1242/42 and/or C1253/53 first.

for C1241/41 and C1242/42: Click here

for C1253/53: Click here

PROCEDURE


  1. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY


    1. Replace the skid control ECU (brake booster with master cylinder assembly).


      Result
      Proceed to
      NEXT

    NEXT

    END