Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Diagnosis System

DIAGNOSIS SYSTEM

DESCRIPTION

The main body ECU (multiplex network body ECU) stores DTCs when malfunctions occur.

The diagnostic system allows for reading of the DTCs from the DLC3.

Use the Techstream to check for malfunctions and perform repairs.

CHECK DLC3

(a) Check the DLC3.

Click here

INSPECT BATTERY VOLTAGE

(a) Measure the vehicle battery voltage.

Standard Voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery.

SELF-DIAGNOSTIC MODE (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 / Smart Access / Utility / Wireless Door Lock Diagnosis Mode.

Body Electrical > Smart Access > Utility

Tester Display

Wireless Door Lock Diagnosis Mode

(e) Proceed to the next step in accordance with the prompts on the Techstream screen.

(f) Check that the system has switched to self-diagnostic mode by checking the wireless door lock buzzer output pattern.

(g) Check the diagnostic output when an electrical key transmitter sub-assembly switch is pressed. The diagnostic outputs can be checked by the interior light blinking pattern and wireless door lock buzzer pattern.

Result

Wireless Door Lock Buzzer Output

Suspected Area

A

Normal (No malfunction)

B

Register electrical key transmitter sub-assembly

C

Wave interference or malfunction of a related component

    Terminals Of Ecu
    TERMINALS OF ECU CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junc ...

    Dtc Check / Clear
    DTC CHECK / CLEAR CHECK DTC (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 / Smart Access / Trou ...

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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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