Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Clearance Warning ECU Communication Stop Mode

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Power Source & Network / Networking / Can Communication System / Clearance Warning ECU Communication Stop Mode

DESCRIPTION

Detection Item

Symptom

Trouble Area

Clearance Warning ECU Communication Stop Mode

Either condition is met:

  • "Clearance Warning (Intuitive Parking Assist)" is not displayed on the CAN Bus Check screen of the Techstream.

    Click here

  • Communication system DTCs (DTCs that start with U) that correspond to "Clearance Warning ECU Communication Stop Mode" in "DTC Combination Table" are output.

    Click here

  • Clearance warning ECU assembly branch line or connector
  • Power source circuit of clearance warning ECU assembly
  • Clearance warning ECU assembly ground circuit
  • Clearance warning ECU assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Before measuring the resistance of the CAN bus, turn the engine switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
  • After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
  • DTC check procedure: Turn the engine switch on (IG) and wait for at least 14 seconds.
  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

  • Operating the engine switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE

1.

CHECK FOR OPEN IN CAN BUS LINES (CLEARANCE WARNING ECU ASSEMBLY BRANCH LINE)

(a) Disconnect the cable from the negative (-) battery terminal.

(b) Disconnect the J38 clearance warning ECU assembly connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

J38-17 (R1) - J38-18 (R2)

Cable disconnected from negative (-) battery terminal

54 to 69 Ω

*a

Front view of wire harness connector

(to Clearance Warning ECU Assembly)
NG

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (CLEARANCE WARNING ECU ASSEMBLY)
OK

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

J38-30 (E) - Body ground

Cable disconnected from negative (-) battery terminal

Below 1 Ω

*a

Front view of wire harness connector

(to Clearance Warning ECU Assembly)

(b) Reconnect the cable to the negative (-) battery terminal.

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

J38-1 (IG) - Body ground

Engine switch on (IG)

11 to 14 V
OK

REPLACE CLEARANCE WARNING ECU ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
    Brake Actuator (Skid Control ECU) Communication Stop Mode
    DESCRIPTION Detection Item Symptom Trouble Area Brake Actuator (Skid Control ECU) Communication Stop Mode Either condition is met: "Skid Control (ABS/VSC/TRAC)" is not displayed on the ...

    Air Conditioning Amplifier Communication Stop Mode
    DESCRIPTION Detection Item Symptom Trouble Area Air Conditioning Amplifier Communication Stop Mode Either condition is met: "Air Conditioning Amplifier" is not displayed on the CAN Bus ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Intelligent Clearance Sonar System: Stop Light Relay Circuit (C1A4B)
    DESCRIPTION When a stop light relay circuit malfunction signal sent from the vehicle stability control system is detected by the clearance warning ECU assembly, DTC C1A4B is stored. DTC No. Detection Item DTC Detection Condition Trouble Area C1A4B Stop Light Relay Circuit Stop light ...

    Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Charging System: Dtc Check / Clear
    DTC CHECK / CLEAR CHECK 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: Powertrain / Engine / Trouble Codes. (e) Check for DTCs, and then write them down. (f) Check the details of the DTCs. Click here Power ...

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

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

    © 2025 Copyright www.lexusrx.net
    0.0138