Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Front Fog Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the front fog lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

    Click here

PROCEDURE

1.

CHECK OPERATION (TAILLIGHTS)

(a) Check the operation of the taillights.

OK:

Taillights operate normally.

NG

GO TO PROBLEM SYMPTOMS TABLE

OK

2.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Main Body / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Main Body > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Front Fog Light Relay

Front fog lights

OFF/ON

Light control switch in tail position

Body Electrical > Main Body > Active Test

Tester Display

Front Fog Light Relay

OK:

Front fog light relay operates. (Front fog lights come on.)

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

3.

CHECK SEMICONDUCTOR POWER INTEGRATION ECU

(a) Using a voltmeter, check the signal reading of the semiconductor power integration ECU.

Click here

OK:

Output signal reading is normal.

NG

INSPECT SEMICONDUCTOR POWER INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK)

OK

4.

CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR POWER INTEGRATION ECU POWER SOURCE AND BODY GROUND)

*a

Component without semiconductor power integration ECU connected

(Engine Room Relay Block and Junction Block Assembly)

-

-

(a) Remove the semiconductor power integration ECU from the engine room relay block and junction block assembly.

Click here

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

A-1 (ALT) - Body ground

Always

11 to 14 V

B-1 (BATT) - Body ground

Always

11 to 14 V

1D-11 (FMIG) - Body ground

Engine switch on (IG)

11 to 14 V

1E-4 (TAIL) - Body ground

Light control switch in tail or head position

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1D-14 (GND1) - Body ground

Always

Below 1 Ω

1G-5 (GND2) - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.

CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR POWER INTEGRATION ECU - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the 2C instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1D-7 (-S) - 2C-25

Always

Below 1 Ω

1D-7 (-S) or 2C-25 - Body ground

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

6.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

*a

Component without harness connected

(Instrument Panel Junction Block Assembly)

-

-

(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

Click here

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2C-25 - MB-7 (FFGO)

Always

Below 1 Ω

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

OK

7.

REPLACE SEMICONDUCTOR POWER INTEGRATION ECU

(a) Replace the semiconductor power integration ECU with a new one.

Click here

NEXT

8.

CHECK OPERATION (FRONT FOG LIGHTS)

(a) Check the operation of the front fog lights.

OK:

Front fog lights operate normally.

OK

END (SEMICONDUCTOR POWER INTEGRATION ECU WAS DEFECTIVE)

NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    Parking Light/Daytime Running Light Circuit
    DESCRIPTION Parking light function: When the main body ECU (multiplex network body ECU) receives the light control switch position signal, it sends an illumination request signal to the No. 1 headl ...

    Turn Signal Light Circuit
    DESCRIPTION The combination meter assembly controls the illumination and turning off of the rear turn signal lights. WIRING DIAGRAM PROCEDURE 1. CHECK OPERATION (REAR TURN SIGNAL LIGHTS) (a) ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Generator (for 180 A Type): Installation
    INSTALLATION PROCEDURE 1. INSTALL GENERATOR ASSEMBLY (a) Install the wire harness clamp bracket with the bolt. Torque: 8.4 N·m {86 kgf·cm, 74 in·lbf} (b) Type A: (1) Install the generator assembly with the 2 bolts. Torque: 43 N·m {438 kgf·cm, 32 ft·lbf} (2) Temporarily install the generator ...

    Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Vehicle Stability Control System: Slip Indicator Light Remains ON
    DESCRIPTION This procedure is for troubleshooting when the slip indicator light remains on but no DTCs are output. The skid control ECU (brake actuator assembly) controls the slip indicator light in the combination meter assembly via CAN communication. The slip indicator light blinks during VSC and/ ...

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

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

    © 2024 Copyright www.lexusrx.net
    0.0111