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Inspection Procedure

NOTE: The inspection procedure is based on the premise that the headlights light up normally whenever the light control switch is operated. If headlight operation is not normal when the light control switch is operated, proceed to PROBLEM SYMPTOM INDEX  table.
NOTE: If not using the hand-held tester, start the inspection from step  2.
  1. Connect the hand-held tester to the DLC3. See Figure. Check that the headlight relay can operate in an ACTIVE TEST. If the headlight relay is normal, the headlights come ON. If the headlight relay activates but the headlights will not come on, check the headlight circuit. If the results are OK, proceed to the next circuit inspection of the symptom. See PROBLEM SYMPTOM INDEX  table. If the results are not good, go to the next step.
  2. Disconnect the theft deterrent ECU connector. Measure the voltage between terminal T5-1 (HEAD) of the theft deterrent ECU and body ground. See CONNECTOR IDENTIFICATION . If voltage is between 10-14 volts, check and replace the theft deterrent ECU. If the voltage is not as specified, check and repair the harness and connector between the theft deterrent ECU and headlight control relay.
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