LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 159 (Multiplex Communication System) >> Diagnostic Tests >> DTC B1244/44: Light Sensor Circuit Malfunction >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedure

WARNING: This page is about a different car, the 2003 Lexus GS 430, 2003 Lexus GS 300, 2002 Lexus GS 430, and 2002 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check the light sensor by connecting the hand-held tester to the DLC3. Turn the ignition switch ON and the hand-held tester main switch ON. Check that the value of the illumination rate should change in the following range (0.8-22.0 ms) when the light sensor is put in the light or covered by a hand. This is the time to be taken for the light sensor to generate one circle of frequency according to the brightness. When not using the hand-held tester, see the AUTOMATIC HEADLIGHTS & LIGHTING article under HEADLIGHTS in ACCESSORIES & EQUIPMENT. If the results are OK, go to the next step. If the results are not good, replace the light sensor. See AUTOMATIC HEADLIGHTS & LIGHTING article under HEADLIGHTS in ACCESSORIES & EQUIPMENT.
  2. Check the wiring harness and connector between the light sensor and body ECU No. 2. See WIRING DIAGRAMS . If the results are OK, replace the body ECU No. 2. See BODY ECU NO. 2  under REMOVAL & INSTALLATION. If the results are not good, repair or replace the wiring harness or connector. See WIRING DIAGRAMS .
  3. After repairs have been made, perform confirmation test. See CONFIRMATION TEST  under SELF-DIAGNOSTIC SYSTEM.
scientia non olet · About LEMON Manuals