2023 Lexus LX 600 BaseFACTORY OEM SERVICE PROCEDURE

Adaptive High Beam System

ADAPTIVE HIGH BEAM SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTC Code Description
B2440-87 AHS Driver LH Missing Message
B2441-87 AHS Driver RH Missing Message
B2490-96 AHS Fan LH Component Internal Failure
B2491-96 AHS Fan RH Component Internal Failure
B2492-00 AHS Driver LH Malfunction
B2493-00 AHS Driver RH Malfunction
U0100-87 Lost Communication with ECM/PCM "A" Missing Message
U0101-87 Lost Communication with TCM Missing Message
U0126-87 Lost Communication with Steering Angle Sensor Module Missing Message
U0129-87 Lost Communication with Brake System Control Module Missing Message
U0140-87 Lost Communication with Body Control Module Missing Message
U0182-87 Lost Communication with Lighting Control Module Front Missing Message
U0235-87 Lost Communication with Cruise Control Front Distance Range Sensor Signal Sensor or Center Missing Message
U023A-87 Lost Communication with Image Processing Module "A"
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.