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DTC C1377/43 Capacitor Malfunction: Description

The brake control power supply (capacitor) is used as auxiliary power for brake control when battery voltage is low.

DTC DETECTION CONDITION

DTC Code Information Code DTC Detection Condition Trouble Area
C1377/43 101 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Brake control power supply is deteriorated (indicates a need to replace).
Brake control power supply
102 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Self-discharge (current leak) is excessive (internal malfunction).
103 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Overvoltage (16.4 V or more) continues to be applied from the battery to the brake control power supply voltage input (+BC) for 10 seconds or more.
Positive battery circuit (Apply high voltage)
105 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Circuit inside the power back up unit (charge) is malfunctioning.
Brake control power supply
106 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Circuit inside the power back up unit (back up output circuit) is malfunctioning.
108 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Circuit inside the power back up unit (voltage monitor circuit) is malfunctioning.
109 When both conditions below are met:
  • IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  • Open circuit between battery (12 V) and brake control power supply power input (+BC terminal).
  • ABS MAIN4 fuse
  • Wire harness or connector
110 When both conditions below are met:
  1. IG1 terminal voltage is 9.5 V or more, and malfunction signal (not capacitor communication malfunction) reception condition continues for 3 sec. or more
  2. When either of the following is detected:
    • Open or short circuit between battery (12 V) and brake control power supply output 1 (OUT1).
    • Open or short circuit between battery (12 V) and brake control power supply output 2 (OUT2).
  • ABS MAIN4 fuse
  • Wire harness or connector