LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2003 >> LS 430 >> Repair and Diagnosis >> Accessories & Equipment >> Communication Devices >> Body Control Systems >> Circuit Tests >> Headlight Circuit >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

  1. Connect the LEXUS hand-held tester to the DLC3. See Figure. Check the headlight using ACTIVE TEST. If the results are OK, proceed to the next circuit inspection of the problem symptom. See PROBLEM SYMPTOM INDEX (BODY NO. 5 CONTROL SYSTEM)  table. If the results are not good, go to the next step.
  2. Check the continuity of the H-LP HI fuse (20-amp) located in the engine room No. 1 relay block. If there is continuity, go to the next step. If there is not continuity, replace the fuse.
  3. Turn the ignition switch OFF. Disconnect the light control (body No. 5) ECU connector. Measure the voltage between terminal No. 12 (FHHI) and No. 25 (E) of the light control (body No. 5) ECU connector. See CONNECTOR IDENTIFICATION . If there is voltage of 10-14 volts, proceed to the next circuit inspection of the problem symptom. See PROBLEM SYMPTOM INDEX (BODY NO. 5 CONTROL SYSTEM)  table. If the voltage is not as specified, go to the next step.
  4. Check the headlight bulb. If the bulb is OK, go to the next step. If the bulb is not good, replace it.
  5. Check the wiring harness and connector between the headlight and front light (body No. 5) ECU, battery and headlight. See WIRING DIAGRAMS . If the results are OK, proceed to the next circuit inspection of the problem symptom. See PROBLEM SYMPTOM INDEX (BODY NO. 5 CONTROL SYSTEM)  table. If the results are not good, repair or replace the wiring harness or connector.
scientia non olet · About LEMON Manuals