Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Lost Communication With ECM/PCM "A" (U0100,...,U1126)

Lexus RX (RX 350L, RX450h) 2016-2025 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.

PROCEDURE

CLEAR DTC

(a) Connect the Techstream to the DLC3.

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

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

(e) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

2.	CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

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

(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.

USE SIMULATION METHOD TO CHECK

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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Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Power Mirror Control System (w/o Memory): Power Mirror cannot be Adjusted with Power Mirror Switch
DESCRIPTION The multiplex network master switch assembly sends the mirror adjust switch signals to the main body ECU (multiplex network body ECU) via LIN communication. The main body ECU (multiplex network body ECU) then sends the received mirror adjust switch signals to each outer mirror control EC ...

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Power Mirror Control System (w/ Memory): Problem Symptoms Table
PROBLEM SYMPTOMS TABLE NOTICE: If the battery voltage is low, the mirror heater function may not operate. When "Operation of Electrical Items Restricted." is displayed on the multi-information display in the combination meter assembly, check the Data List item "Battery Control Count (Body ECU)". Cli ...

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Lost Communication With ECM/PCM "A" (U0100,...,U1126)

Control Module Communication Bus Off (U0073,U0100,U0101,U0126,U0129,U0142,U0155)

Lost Communication With ECM/PCM "A" Missing Message (U010087,U012587,U012987,U014087)

Other materials:

Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual

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)