Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Instrument Panel Box Light and Footwell Light Circuit

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Interior / Lighting (int) / Lighting System / Instrument Panel Box Light and Footwell Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the instrument panel box light and footwell light.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

Click here

PROCEDURE

1.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / (desired system) / 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

Fr Foot Light

Footwell light and instrument panel box light

ON or OFF

-

Body Electrical > Main Body > Active Test

Tester Display

Fr Foot Light

OK:

Instrument panel box light and footwell lights comes on.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

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

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

2E-1 - Body ground

Always

11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

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

(b) Disconnect the 2B instrument panel junction block assembly connector.

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

*a

Component without harness connected

(Instrument Panel Junction Block Assembly)

-

-

Standard Resistance:

Tester Connection

Condition

Specified Condition

2E-1 - 2B-24

Always

Below 1 Ω

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

OK

4.

CHECK HARNESS AND CONNECTOR (No. 1 INTERIOR ILLUMINATION LIGHT ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the J13 No. 1 interior illumination light assembly LH connector.

(b) Disconnect the J37 No. 1 interior illumination light assembly RH connector.

(c) Disconnect the J18 No. 1 interior illumination light assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2B-24 - J13-2(B)

Always

Below 1 Ω

2B-24 - J37-2(B)

Always

Below 1 Ω

2B-24 - J18-2(B)

Always

Below 1 Ω

J13-2(B) or 2B-24 - Body ground

Always

10 kΩ or higher

J37-2(B) or 2B-24 - Body ground

Always

10 kΩ or higher

J18-2(B) or 2B-24 - Body ground

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.

CHECK HARNESS AND CONNECTOR (No. 1 INTERIOR ILLUMINATION LIGHT ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the 2A 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

2A-37 - J13-1(E)

Always

Below 1 Ω

2A-37 - J37-1(E)

Always

Below 1 Ω

2A-37 - J18-1(E)

Always

Below 1 Ω

J13-1(E) or 2A-37 - Body ground

Always

10 kΩ or higher

J37-1(E) or 2A-37 - Body ground

Always

10 kΩ or higher

J18-1(E) or 2A-37 - Body ground

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

6.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the instrument panel junction block assembly.

Click here

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

Click here

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

*a

Component without harness connected

(Instrument Panel Junction Block Assembly)

-

-

Standard Resistance:

Tester Connection

Condition

Specified Condition

2A-37 - MB-26 (FSPT)

Always

Below 1 Ω

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

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