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Home >> Toyota >> 2021 >> RAV4 Adventure >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Headlights >> Lighting System (W/O Headlight Ecu) - Diagnostic Codes & Circuit Tests >> LIGHTING SYSTEM (w/o Headlight ECU) >> DTC U0100: Lost Communication With ECM/PCM "A"; DTC U0101: Lost Communication with TCM; DTC U0120: Lost Communication With Starter / Generator Control Module; DTC U0126: Lost Communication with Steering Angle Sensor Module; DTC U0129: Lost Communication with Brake System Control Module; DTC U0151: Lost Communication with Restraints Control Module; DTC U0155: Lost Communication with Instrument Panel Cluster (IPC) Control Module; DTC U0163: Lost Communication with Navigation Control Module; DTC U0164: Lost Communication with HVAC Control Module; DTC U0208: Lost Communication with "Seat Control Module A"; DTC U0230: Lost Communication with Rear Gate Module; DTC U023A: Lost Communication With Image Processing Module "A"; DTC U0327: Software Incompatibility with Vehicle Security Control Module; DTC U1103: Lost Communication with Stop and Start Control Module; DTC U1117: Lost Communication with Accessory Gateway [11/2018 - 02/2019] >> Description
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DTC U0100: Lost Communication With ECM/PCM "A"; DTC U0101: Lost Communication with TCM; DTC U0120: Lost Communication With Starter / Generator Control Module; DTC U0126: Lost Communication with Steering Angle Sensor Module; DTC U0129: Lost Communication with Brake System Control Module; DTC U0151: Lost Communication with Restraints Control Module; DTC U0155: Lost Communication with Instrument Panel Cluster (IPC) Control Module; DTC U0163: Lost Communication with Navigation Control Module; DTC U0164: Lost Communication with HVAC Control Module; DTC U0208: Lost Communication with "Seat Control Module A"; DTC U0230: Lost Communication with Rear Gate Module; DTC U023A: Lost Communication With Image Processing Module "A"; DTC U0327: Software Incompatibility with Vehicle Security Control Module; DTC U1103: Lost Communication with Stop and Start Control Module; DTC U1117: Lost Communication with Accessory Gateway [11/2018 - 02/2019]: Description

These DTCs are stored if a CAN communication malfunction occurs between the main body ECU (multiplex network body ECU) and other ECUs.

DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from Note
U0100 Lost Communication With ECM/PCM "A" The main body ECU (multiplex network body ECU) does not receive data from the ECM for approximately 10 seconds or more.
  • CAN communication system
  • ECM
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0101 Lost Communication with TCM The main body ECU (multiplex network body ECU) does not receive data from the ECM for approximately 10 seconds or more.
  • CAN communication system
  • ECM
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0120 Lost Communication With Starter / Generator Control Module The main body ECU (multiplex network body ECU) does not receive data from the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.
  • CAN communication system
  • Certification ECU (smart key ECU assembly)
  • Main body ECU (multiplex network body ECU)
 Main Body w/ Smart Key System
U0126 Lost Communication with Steering Angle Sensor Module The main body ECU (multiplex network body ECU) does not receive data from the steering sensor for approximately 10 seconds or more.
  • CAN communication system
  • Steering sensor
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0129 Lost Communication with Brake System Control Module The main body ECU (multiplex network body ECU) does not receive data from the brake actuator assembly (skid control ECU) for approximately 10 seconds or more.
  • CAN communication system
  • Brake actuator assembly (skid control ECU)
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0151 Lost Communication with Restraints Control Module The main body ECU (multiplex network body ECU) does not receive data from the airbag ECU assembly for approximately 10 seconds or more.
  • CAN communication system
  • Airbag ECU assembly
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0155 Lost Communication with Instrument Panel Cluster (IPC) Control Module The main body ECU (multiplex network body ECU) does not receive data from the combination meter assembly for approximately 10 seconds or more.
  • CAN communication system
  • Combination meter assembly
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0163 Lost Communication with Navigation Control Module The main body ECU (multiplex network body ECU) does not receive data from the radio and display receiver assembly for approximately 10 seconds or more.
  • CAN communication system
  • Radio and display receiver assembly
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0164 Lost Communication with HVAC Control Module The main body ECU (multiplex network body ECU) does not receive data from the air conditioning amplifier assembly for approximately 10 seconds or more.
  • CAN communication system
  • Air conditioning amplifier assembly
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0208 Lost Communication with "Seat Control Module A" Communication stop occurs between the main body ECU (multiplex network body ECU) and position control ECU assembly continuously for 10 seconds or more.
  • CAN communication system
  • Position control ECU assembly
  • Main body ECU (multiplex network body ECU)
 Main Body w/ Memory
U0230 Lost Communication with Rear Gate Module Communication stop occurs between the main body ECU (multiplex network body ECU) and multiplex network door ECU continuously for 10 seconds or more.
  • CAN communication system
  • Multiplex network door ECU
  • Main body ECU (multiplex network body ECU)
 Main Body w/ Power Back Door System
U023A Lost Communication With Image Processing Module "A" The main body ECU (multiplex network body ECU) does not receive data from the forward recognition camera for approximately 10 seconds or more.
  • CAN communication system
  • Forward recognition camera
  • Main body ECU (multiplex network body ECU)
 Main Body -
U0327 Software Incompatibility with Vehicle Security Control Module The main body ECU (multiplex network body ECU) does not receive data from the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.
  • CAN communication system
  • Certification ECU (smart key ECU assembly)
  • Main body ECU (multiplex network body ECU)
 Main Body w/ Smart Key System
U1103 Lost Communication with Stop and Start Control Module The main body ECU (multiplex network body ECU) does not receive data from the engine stop and start ECU for approximately 10 seconds or more.
  • CAN communication system
  • Engine stop and start ECU
  • Main body ECU (multiplex network body ECU)
 Main Body w/ Stop and Start System
U1117 Lost Communication with Accessory Gateway The main body ECU (multiplex network body ECU) does not receive data from the option connector (bus buffer ECU) for approximately 10 seconds or more.
  • CAN communication system
  • Option connector (bus buffer ECU)
  • Main body ECU (multiplex network body ECU)
 Main Body w/ Bus Buffer ECU
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