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DTC C1377/43 Capacitor Malfunction: Description

The brake control power supply assembly (capacitor) provides auxiliary power for brake control when an auxiliary battery (12 V) voltage drops.

DIAGNOSTIC TROUBLE CODE CHART

DTC No. INF Code DTC Detection Condition Trouble Area
C1377/43 101 Brake control power supply assembly is deteriorated (indicates a need to replace). Brake control power supply
C1377/43 102 Self-discharge (current leak) is excessive (internal malfunction). Brake control power supply
C1377/43 103 Input voltage from the auxiliary battery (12 V) to the brake control power supply is 16.4 V or more for at least 10 sec. Apply high voltage
C1377/43 105 Circuit inside the power back up unit (charge) is malfunctioning. Brake control power supply
C1377/43 106 Circuit inside the power back up unit (back up output circuit) is malfunctioning. Brake control power supply
C1377/43 108 Circuit inside the power back up unit (voltage monitor circuit) is malfunctioning. Brake control power supply
C1377/43 109 Open circuit between auxiliary battery (12 V) and brake control power supply power input (+BC terminal).
  • Harness and connector
  • ABS No.3 fuse
C1377/43 110
  • Open or short circuit between auxiliary battery (12 V) and brake control power supply output 1 (OUT 1).
  • Open or short circuit between auxiliary battery (12 V) and brake control power supply output 2 (OUT 2)
  • Harness and connector
  • ABS No.1 fuse
  • ABS No.2 fuse