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Home >> Lexus >> 2024 >> RX 500h >> Repair and Diagnosis >> External Pages >> Different car >> Section 13 (Can Communication System - Circuit Tests (1 Of 3) & Diagnostic Codes) >> CAN COMMUNICATION SYSTEM (for Gasoline Model) >> DTC U115C-87: Lost Communication with ECM/PCM "A" (ch5) Missing Message; DTC U1170-87: Lost Communication with Brake System Control Module (ch2) Missing Message [10/2022 - ] >> Description

DTC U115C-87: Lost Communication with ECM/PCM "A" (ch5) Missing Message; DTC U1170-87: Lost Communication with Brake System Control Module (ch2) Missing Message [10/2022 - ]: Description

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DTC No. Detection Item DTC Detection Condition Trouble Area Note
U115C-87 Lost Communication with ECM/PCM "A" (ch5) Missing Message Communication stops between the ECM or engine stop and start ECU and the brake actuator assembly.
  • CAN main/branch bus lines or connector
  • ECM
  • Engine stop and start ECU
  • Brake actuator assembly
  • No. 12 CAN junction connector
DTC Output from
  • ECM
  • Engine stop and start ECU
  • Brake actuator assembly
U1170-87 Lost Communication with Brake System Control Module (ch2) Missing Message Communication stops between the engine stop and start ECU or absorber control ECU and the brake actuator assembly.
  • CAN main/branch bus lines or connector
  • Engine stop and start ECU
  • Brake actuator assembly
  • Absorber control ECU
  • No. 12 CAN junction connector
  • No. 20 CAN junction connector
DTC Output from
  • Engine stop and start ECU
  • Absorber control ECU