2003 Lexus GS 300FACTORY OEM SERVICE PROCEDURE

Section 194 (LEXUS Navigation System): Pre-Check

WARNING: This page is about a different car, the 2004 Lexus GS 430 and 2004 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. DIAGNOSIS SYSTEM MODE 

    HINT:

    Diagnosis System Mode is operated as follows.

    Fig 1: Pre-Check Diagnosis Display
    G01484960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. DIAGNOSIS START-UP To start the diagnosis menu, there are 3 ways: using a diagnosis check wire and using a switch.
    2. START-UP BY SWITCH OPERATION (light control switch)
      1. Vehicle speed is 0 km/h (0 mph).
      2. Parking brake switch is pressed.
      3. While pressing "INFO" switch, by turning the light control switch to OFF, TAIL, OFF, TAIL, and OFF the system is started up.
    3. START-UP BY SWITCH OPERATION (touch panel)
      1. Vehicle speed is 0 km/h (0 mph).
      2. Parking brake switch is pressed.
      3. Press the "INFO" switch to display the Screen Adjustment screen.
        Fig 2: Identifying Info Switch
        G01484961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Repeatedly touch the upper and lower bottom parts of the left end of the screen 3 times.
        Fig 3: Identifying Concealed Touch Display
        G01484962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. FINISHING DIAGNOSIS SYSTEM MODE Turn the ignition switch from ACC to OFF to finish the mode. If it is started by switch operation.
  2. SERVICE CHECK MODE 

    HINT:

    Service Check Mode is operated as follows.

    Fig 4: Service Check Mode Display
    G01484963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Service Check Mode
    1. Start the Diagnosis System.
      Fig 5: Service Check Mode Diagnosis System Table
      G01484964Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.