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DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0129: Lost Communication with Brake System Control Module; DTC U0293: Lost Communication with HV ECU: Description

DTC No. DTC Detection Condition Trouble Area
U0100 The power management control ECU does not receive data from the ECM.
  • Open or short in power management main bus wire or connector
  • Open or short in power management bus branch wire or connector
  • Power source circuit of power management control ECU
  • Power management control ECU
  • Power source circuit of ECM
  • ECM
  • Open or short in CAN No. 5 junction connector
U0129 The power management control ECU does not receive data from the brake booster with master cylinder (skid control ECU).
  • Open or short in power management main bus wire or connector
  • Open or short in power management bus branch wire or connector
  • Power source circuit of power management control ECU
  • Power management control ECU
  • Power source circuit of brake booster with master cylinder (skid control ECU)
  • Brake booster with master cylinder (skid control ECU)
  • Open or short in CAN No. 5 junction connector
U0293
  • The ECM does not receive data from the power management control ECU.
  • The brake booster with master cylinder (skid control ECU) does not receive data from the power management control ECU.
  • Open or short in power management main bus wire or connector
  • Open or short in power management bus branch wire or connector
  • Power source circuit of ECM
  • ECM
  • Power source circuit of power management control ECU
  • Power management control ECU
  • Power source circuit of brake booster with master cylinder (skid control ECU)
  • Brake booster with master cylinder (skid control ECU)
  • Open or short in CAN No. 5 junction connector

HINT: 

This diagnosis procedure is for when DTC U0100, U0129 and U0293 are output at the same time.