Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: No. 1 Clearance Warning Buzzer Circuit

DESCRIPTION

This circuit consists of the No. 1 clearance warning buzzer and clearance warning ECU assembly. An ECU-excited type buzzer is used. The ECU operates the buzzers using a sound pattern that changes depending on the distance to the obstacle.

WIRING DIAGRAM

PROCEDURE

1.	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 / Advanced Parking Guidance/ICS/Intuitive P/A / Active Test.

(e) Check that the buzzer operates by performing the Active Test.

Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Front Buzzer	No. 1 clearance warning buzzer	Stop or Operate	Confirm that the vehicle is stopped and the engine switch is on (IG)

Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Active Test

Tester Display
Front Buzzer

OK:

The No. 1 clearance warning buzzer sounds.

OK

REPLACE CLEARANCE WARNING ECU ASSEMBLY

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2.	CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSEMBLY - NO. 1 CLEARANCE WARNING BUZZER)

(a) Disconnect the J38 clearance warning ECU assembly connector.

(b) Disconnect the J17 No. 1 clearance warning buzzer connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
J38-14 (CBZ) - J17-1 (Z+)	Always	Below 1 Ω
J38-13 (EF) - J17-2 (Z-)	Always	Below 1 Ω
J38-14 (CBZ) or J17-1 (Z+) - Body ground	Always	10 kΩ or higher
J38-13 (EF) or J17-2 (Z-) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.	REPLACE NO. 1 CLEARANCE WARNING BUZZER

(a) Replace the No. 1 clearance warning buzzer with a new or known good one.

Click here

NEXT

4.	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 / Advanced Parking Guidance/ICS/Intuitive P/A / Active Test.

(e) Check that the buzzer operates by performing the Active Test.

Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Front Buzzer	No. 1 clearance warning buzzer	Stop or Operate	Confirm that the vehicle is stopped and the engine switch is on (IG)

Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Active Test

Tester Display
Front Buzzer

OK:

The No. 1 clearance warning buzzer sounds.

OK

END

NG

REPLACE CLEARANCE WARNING ECU ASSEMBLY