Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Lost Communication With ECM/PCM "A" (U0100,...,U1126)

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Vehicle Exterior / Lighting (ext) / Lighting System (w/ Automatic Headlight Beam Level Control System) / Lost Communication With ECM/PCM "A" (U0100,...,U1126)

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

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)

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)

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)

U0129

Lost Communication with Brake System Control Module

The main body ECU (multiplex network body ECU) does not receive data from the skid control ECU (brake actuator assembly) for approximately 10 seconds or more.
  • CAN communication system
  • Skid control ECU (brake actuator assembly)

Main body ECU (multiplex network body ECU)

U0151

Lost Communication with Restraints Control Module

The main body ECU (multiplex network body ECU) does not receive data from the airbag sensor assembly for approximately 10 seconds or more.
  • CAN communication system
  • Airbag sensor assembly

Main body ECU (multiplex network body ECU)

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)

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)

U0182

Lost Communication with AFS

The main body ECU (multiplex network body ECU) does not receive data from the No. 1 headlight ECU sub-assembly LH for approximately 10 seconds or more.
  • CAN communication system
  • No. 1 headlight ECU sub-assembly LH

Main body ECU (multiplex network body ECU)

U0199

Lost Communication with "Door Control Module A"

The main body ECU (multiplex network body ECU) does not receive data from the outer mirror control ECU assembly LH for approximately 10 seconds or more.
  • CAN communication system
  • Outer mirror control ECU assembly LH

Main body ECU (multiplex network body ECU)

U0200

Lost Communication with "Door Control Module B"

The main body ECU (multiplex network body ECU) does not receive data from the outer mirror control ECU assembly RH for approximately 10 seconds or more.
  • CAN communication system
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

U0208

Lost Communication with "Seat Control Module A"

The main body ECU (multiplex network body ECU) does not receive data from the position control ECU and switch assembly LH for approximately 10 seconds or more.
  • CAN communication system
  • Position control ECU and switch assembly LH

Main body ECU (multiplex network body ECU)

U0230

Lost Communication with Rear Gate Module

The main body ECU (multiplex network body ECU) does not receive data from the multiplex network door ECU for approximately 10 seconds or more.
  • CAN communication system
  • Multiplex network door ECU

Main body ECU (multiplex network body ECU)

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)

U0265

Lost Communication with Parking Assist Monitor Module

The main body ECU (multiplex network body ECU) does not receive data from the rear television camera assembly for approximately 10 seconds or more.
  • CAN communication system
  • Rear television camera assembly

Main body ECU (multiplex network body ECU)

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)

U1002

Lost Communication with Gateway Module

The main body ECU (multiplex network body ECU) detects communication errors between itself and the position control ECU and switch assembly LH, outer mirror control ECU assembly (for front passenger side), outer mirror control ECU assembly (for driver side), multiplex network door ECU and multiplex tilt and telescopic ECU.
  • CAN communication system
  • Position control ECU and switch assembly LH
  • Outer mirror control ECU assembly (for front passenger side)
  • Outer mirror control ECU assembly (for driver side)
  • Multiplex network door ECU
  • Multiplex tilt and telescopic ECU

Main body ECU (multiplex network body ECU)

U1106

Lost Communication with Electric Parking Brake Module

The main body ECU (multiplex network body ECU) does not receive data from the skid control ECU (brake actuator assembly) for approximately 10 seconds or more.
  • CAN communication system
  • Skid control ECU (brake actuator assembly)

Main body ECU (multiplex network body ECU)

U1115

Lost Communication with Tilt & Telescopic Module

The main body ECU (multiplex network body ECU) does not receive data from the multiplex tilt and telescopic ECU for approximately 10 seconds or more.
  • CAN communication system
  • Multiplex tilt and telescopic ECU

Main body ECU (multiplex network body ECU)

U1126

Lost Communication with Parking Assist Monitor Module

The main body ECU (multiplex network body ECU) does not receive data from the rear television camera assembly for approximately 10 seconds or more.
  • CAN communication system
  • Rear television camera assembly

Main body ECU (multiplex network body ECU)

PROCEDURE

1.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Main Body / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs
NEXT

2.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Wait 20 seconds or more.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / Main Body / Trouble Codes.

(f) Check for DTCs.

Body Electrical > Main Body > Trouble Codes

OK:

DTCs are not output.

OK

USE SIMULATION METHOD TO CHECK

NG

GO TO CAN COMMUNICATION SYSTEM

    Control Module Communication Bus Off (U0073,U0100,U0101,U0126,U0129,U0142,U0155)
    DESCRIPTION These DTCs are stored if a CAN communication malfunction occurs between the No. 1 headlight ECU sub-assembly LH and other ECUs. DTC No. Detection Item DTC Detection Condition Trou ...

    Lost Communication With ECM/PCM "A" Missing Message (U010087,U012587,U012987,U014087)
    DESCRIPTION These DTCs are stored if a CAN communication malfunction occurs between the forward recognition camera and other ECUs. DTC No. Detection Item DTC Detection Condition Trouble Area ...

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