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Home >> Lexus >> 2017 >> RX 350 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Exterior Lights >> Lighting System (W/ Automatic Headlight Beam Level Control System) - Diagnostic Codes >> LIGHTING SYSTEM (w/ Automatic Headlight Beam Level Control System) >> DTC B1244: Light Sensor Circuit [08/2019 - ] >> Description
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DTC B1244: Light Sensor Circuit [08/2019 - ]: Description

The automatic light control sensor detects ambient light. The sensor creates an electrical signal based on the amount of light detected, and sends the signal to the main body ECU (multiplex network body ECU). The main body ECU (multiplex network body ECU) turns on or off the headlights and taillights according to the signal.

DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from
B1244 Light Sensor Circuit Detection condition: 
  1. The engine switch is on (IG).

Malfunction status: 
  1. Either of the following conditions is met:
    • Malfunction in automatic light control sensor
    • Open or short in automatic light control sensor circuit

Malfunction duration: 
  1. 5 seconds or more
  • Automatic light control sensor
  • Harness or connector
  • Main body ECU (multiplex network body ECU)
Main Body