Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter

Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual / Audio & Visual & Telematics / Audio / Video / Audio And Visual System (for 12.3 Inch Display) / Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter

DESCRIPTION

The stereo component amplifier assembly receives a vehicle speed signal from the combination meter assembly to control the ASL function.

HINT:

  • A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the transistor in the combination meter assembly. Each ECU controls its respective systems based on this pulse signal.
  • If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the following diagram will not operate normally.

WIRING DIAGRAM

PROCEDURE

1.

INSPECT COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)

(a) Check the output waveform.

(1) Remove the combination meter assembly with the connector(s) still connected.

(2) Connect an oscilloscope to terminal J10-19 (+S) and body ground.

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

(4) Turn a wheel slowly.

(5) Check the signal waveform according to the condition(s) in the table below.

Item

Condition

Measurement terminal

J10-19 (+S) - Body ground

Tool setting

5 V/DIV., 20 ms./DIV.

Vehicle condition

Wheel being rotated

OK:

The waveform is similar to that shown in the illustration.

HINT:

When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

*a

Component with harness connected

(Combination Meter Assembly)

NG

GO TO METER / GAUGE SYSTEM

OK

2.

INSPECT STEREO COMPONENT AMPLIFIER ASSEMBLY (INPUT WAVEFORM)

(a) Check the input waveform.

(1) Remove the stereo component amplifier assembly with the connector(s) still connected.

(2) Connect an oscilloscope to terminal J66-17 (SPD) and body ground.

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

(4) Turn a wheel slowly.

(5) Check the signal waveform according to the condition(s) in the table below.

Item

Condition

Measurement terminal

J66-17 (SPD) - Body ground

Tool setting

5 V/DIV., 20 ms./DIV.

Vehicle condition

Wheel being rotated

OK:

The waveform is similar to that shown in the illustration.

HINT:

When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

*a

Component with harness connected

(Stereo Component Amplifier Assembly)

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (COMBINATION METER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)

    Vehicle Speed Signal Circuit between Navigation ECU and Combination Meter
    DESCRIPTION The navigation ECU receives a vehicle speed signal from the combination meter assembly. HINT: A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter as ...

    Reverse Signal Circuit between Radio Receiver Assembly and Navigation ECU
    DESCRIPTION This circuit includes the navigation ECU and radio receiver assembly. WIRING DIAGRAM PROCEDURE 1. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - NAVIGATION ECU) (a) Disco ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Name Plate: Installation
    INSTALLATION CAUTION / NOTICE / HINT HINT: When installing the name plates, heat the vehicle body and name plates using a heat light. Heating Temperature Item Temperature Vehicle Body 40 to 60°C (104 to 140°F) Name Plate 20 to 30°C (68 to 86°F) CAUTION: Do not touch the he ...

    Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Audio And Visual System (for 8 Inch Display): Lost Communication with Haptic Device (B1323-B1326)
    DESCRIPTION These DTCs are stored when communication between the radio receiver assembly and remote touch (remote operation controller assembly), combination meter assembly, headup display (meter mirror sub-assembly)* or clock assembly is not possible. *: w/ Headup Display System DTC No. ...

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

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

    © 2024 Copyright www.lexusrx.net
    0.0173