Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Air Conditioning Control Panel Circuit

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Interior / Heating / Air Conditioning / Air Conditioning System / Air Conditioning Control Panel Circuit

DESCRIPTION

The radio receiver assembly (A/C control panel) switch signals are sent to the air conditioning amplifier assembly via CAN communication.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

CHECK CAN COMMUNICATION SYSTEM

(a) Using the Techstream, check if the CAN communication system is functioning normally.

Click here

Result

Proceed to

CAN communication system DTCs are not output

A

CAN communication system DTCs are output

B
B

GO TO CAN COMMUNICATION SYSTEM

A

2.

CHECK AVC-LAN COMMUNICATION CIRCUIT

(a) Check for an open or short in all AVC-LAN communication circuits.

w/ Navigation System: Click here

w/ Audio and Visual System (for 12.3 Inch Display): Click here

w/ Audio and Visual System (for 8 Inch Display): Click here

OK:

There is no open or short circuit.

NG

REPAIR AVC-LAN COMMUNICATION CIRCUIT
OK

3.

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY (A/C CONTROL PANEL) - POWER SOURCE AND BODY GROUND)

(a) Disconnect the J148 and J149 radio receiver assembly (A/C control panel) connectors.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

J149-19 (IG) - Body ground

Engine switch on (IG)

11 to 14 V

J148-15 (ACC1) - Body ground

Engine switch on (ACC)

11 to 14 V

J148-4 (+B1) - Body ground

Always

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J148-1 (GND1) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (MULTI-DISPLAY ASSEMBLY - POWER SOURCE AND BODY GROUND)

(a) Disconnect the J56 multi-display assembly connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

J56-24 (ACC) - Body ground

Engine switch on (ACC)

11 to 14 V

J56-12 (B) - Body ground

Always

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J56-13 (GND1) - Body ground

Always

Below 1 Ω
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
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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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