Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Problem Symptoms Table

PROBLEM SYMPTOMS TABLE

HINT:

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

Horn System

Symptom

Suspected Area

Link

Horn does not sound

HORN fuse

-

HORN relay

Horn button assembly

Steering pad switch assembly

Spiral cable with sensor sub-assembly

Instrument panel junction block assembly

Harness or connector

-

Horn sounds all the time

HORN relay

Horn button assembly

Steering pad switch assembly

Spiral cable with sensor sub-assembly

Instrument panel junction block assembly

Main body ECU (Multiplex network body ECU)

Harness or connector

-

Low pitched horn operates but high pitched horn does not operate

High pitched horn assembly

Harness or connector

-

High pitched horn operates but low pitched horn does not operate

Low pitched horn assembly

Harness or connector

-

    System Diagram
    SYSTEM DIAGRAM ...

    Data List / Active Test
    DATA LIST / ACTIVE TEST PERFORM ACTIVE TEST HINT: Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrus ...

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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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