Skip to main content
This guide provides step-by-step instructions on how to read Lexus fault codes via the diagnostic port.

Table of Contents

What you will need

The procedure is the same regardless of the scanner being used. 

Codes from the Engine Control Unit (ECU) can be read with a basic scanner.

Codes from the transmission, airbag, anti-lock brakes, traction control, require a multi-system scanner. 


  1. Locate the OBD connector under the dashboard on the driver's side. OBD port
  2. Connect your OBDII reader to the OBD connectorScanner Connected


  3. Turn your key in the ignition with two clicks.2 click ignition On vehicles with Start/Stop, press the button twice without touching the brake pedal. Push Start Ignition


  4. Allow the scanner to power on and select your Lexus model. Scanner Lexus Model


  5. Select Auto Scan or Full System Scan to read fault codes from all the modules. Or select Control Units to pick the system you want to diagnose. Scanning


  6. Select Read Fault codes. A list of fault codes will be displayed on the scanner. Reading Codes


Codes that show up as PRESENT or CURRENT need to be addressed. 

Codes that show as STORED or PAST or HISTORY mean that they existed in the past but are not currently an issue. They can help you troubleshoot challenging problems.