Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Lost Communication with ECM / PCM "A" (U0100,U0142,U0163,U023A)

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Vehicle Interior / Meter / Gauge / Display / Headup Display System / Lost Communication with ECM / PCM "A" (U0100,U0142,U0163,U023A)

DESCRIPTION

The headup display (meter mirror sub-assembly) communicates with the ECM, main body ECU (multiplex network body ECU), radio receiver assembly and forward recognition camera via CAN communication.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

Note

U0100

Lost Communication with ECM / PCM "A"

Diagnosis Condition:

  • The engine switch is on (IG)
  • IG power source voltage is 9.5 V or more

Malfunction Status:

  • No communication with ECM

Malfunction Time:

  • 2 seconds or more
  • ECM
  • CAN communication system
  • Headup display (Meter mirror sub-assembly)

DTC stored

-

U0142

Lost Communication with Body Control Module "B"

Diagnosis Condition:

  • The engine switch is on (IG)
  • IG power source voltage is 9.5 V or more

Malfunction Status:

  • No communication with main body ECU (multiplex network body ECU)

Malfunction Time:

  • 3 seconds or more
  • Main body ECU (multiplex network body ECU)
  • CAN communication system
  • Headup display (Meter mirror sub-assembly)

DTC stored

-

U0163

Lost Communication with Navigation Control Module

Diagnosis Condition:

  • The engine switch is on (IG)
  • IG power source voltage is 9.5 V or more

Malfunction Status:

  • No communication with radio receiver assembly

Malfunction Time:

  • 3 seconds or more
  • Radio receiver assembly
  • CAN communication system
  • Headup display (Meter mirror sub-assembly)

-

-

U023A

Lost Communication with Front Camera Module

Diagnosis Condition:

  • The engine switch is on (IG)
  • IG power source voltage is 9.5 V or more

Malfunction Status:

  • 10 seconds or more
  • Forward recognition camera
  • CAN communication system
  • Headup display (Meter mirror sub-assembly)

DTC stored

-

PROCEDURE

1.

CHECK CAN COMMUNICATION SYSTEM

(a) Check if CAN communication DTCs are output.

Click here

Result

Proceed to

CAN communication DTCs are output

A

CAN communication DTCs are not output

B
A

GO TO CAN COMMUNICATION SYSTEM

B

USE SIMULATION METHOD TO CHECK

    Lost Communication with EMV (B1321)
    DESCRIPTION After the headup display (meter mirror sub-assembly) has started, the headup display (meter mirror sub-assembly) attempts to detect the radio receiver assembly by performing communication ...

    Main Switch Circuit
    DESCRIPTION The headup display switch assembly (integration control and panel assembly) and headup display (meter mirror sub-assembly) are connected via direct line. The headup display (meter mirror s ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Automatic Transaxle System: Diagnosis System
    DIAGNOSIS SYSTEM DESCRIPTION (a) When troubleshooting On-Board Diagnostic (OBD II) vehicles, an OBD II scan tool (complying with SAE J1978) must be connected to the vehicle. Various data output from the vehicle ECM can then be read. (b) OBD II regulations require that the vehicle on-board computer i ...

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