2008 Lexus IS 350FACTORY OEM SERVICE PROCEDURE

Diagnostic Trouble Code Chart

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
  1. POWER SOURCE CONTROL ECU DIAGNOSTIC TROUBLE CODE CHART 

    Power Source Control ECU 

    DIAGNOSTIC TROUBLE CODE CHART

    DTC Code Detection Item Trouble Area
    B2287  LIN Communication Master Malfunction
    1. Power source control ECU
    2. Certification ECU (smart key ECU assembly)
    3. Wire harness or connector
  2. CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) DIAGNOSTIC TROUBLE CODE CHART 

    Certification ECU (Smart Key ECU Assembly) 

    DIAGNOSTIC TROUBLE CODE CHART

    DTC Code Detection Item Trouble Area
    B2785  Communication Malfunction between ECUs Connected by LIN
    1. Certification ECU (smart key ECU assembly)
    2. Power source control ECU
    3. Steering lock ECU (steering lock actuator assembly)
    4. ID code box (immobilizer code ECU)
    5. Wire harness or connector
    B2786  No Response from Steering Lock ECU
    1. Steering lock ECU (steering lock actuator assembly)
    2. Certification ECU (smart key ECU assembly)
    3. Wire harness or connector
    4. Fuse
    B2789  No Response from ID BOX
    1. ID code box (immobilizer code ECU)
    2. Certification ECU (smart key ECU assembly)
    3. Wire harness or connector
    4. Fuse
Factory Service Tools

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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.