LEMON Manuals: Even more car manuals for everyone
Home >> Toyota >> 2019 >> Mirai >> Repair and Diagnosis (Single Page) >> Brakes >> Mechanical - Hydraulic >> Electronically Controlled Brake System - Diagnostic Codes (1 Of 2) >> Electronically Controlled Brake System >> DTC C1257-57: Power Supply Drive Circuit [06/2015 - ] >> Description

DTC C1257-57: Power Supply Drive Circuit [06/2015 - ]: 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