Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

  • Use the following procedure to troubleshoot the LIN communication system.
  • *: Use the Techstream.

PROCEDURE

1.

VEHICLE BROUGHT TO WORKSHOP

NEXT

2.

CUSTOMER PROBLEM ANALYSIS

HINT:

  • In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
  • Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
  • The following 5 items are important points for problem analysis:

What

Vehicle model, system name

When

Date, time, occurrence frequency

Where

Road conditions

Under what conditions?

Driving conditions, weather conditions

How did it happen?

Problem symptoms

NEXT

3.

PRE-CHECK

(a) Measure the battery voltage.

Standard Voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.

(b) Check the fuses and relays.

(c) Check the connectors and terminals to make sure that there are no abnormalities such as a loose connection or deformation.

NEXT

4.

INSPECT COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM*

(a) Using the Techstream, check for CAN communication system DTCs.

Click here

Result

Proceed to

CAN DTCs are not output

A

CAN DTCs are output

B

B

GO TO CAN COMMUNICATION SYSTEM

A

5.

INSPECT COMMUNICATION FUNCTION OF LIN COMMUNICATION SYSTEM*

(a) Using the Techstream, check for LIN communication system DTCs.

Click here

Result

Proceed to

LIN DTCs are not output

A

LIN DTCs are output

B

B

GO TO DIAGNOSTIC TROUBLE CODE CHART

A

6.

OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Terminals of ECU

Click here

(b) Data List / Active Test

Click here

NEXT

7.

REPAIR OR REPLACE

NEXT

8.

CONFIRMATION TEST

NEXT

END

    System Description
    SYSTEM DESCRIPTION LIN COMMUNICATION SYSTEM DESCRIPTION The LIN communication system is used for communication between the components in the tables below. If communication cannot be performed through ...

    Diagnosis System
    DIAGNOSIS SYSTEM DESCRIPTION The main body ECU (multiplex network body ECU) and certification ECU (smart key ECU assembly) control the LIN communication system. LIN communication system data and Diagn ...

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

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

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