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Inspection Procedure

For circuit wiring diagram, see Fig 1.

NOTE: If using the hand-held tester, start the inspection from step  1 and if not using the hand-held tester, start from step  2.
  1. Check the taillight relay using the hand-held tester. Connect the hand-held tester to DLC3. See Figure. Check that the taillight relay can operate in ACTIVE TEST. If the results are OK, perform the next test procedure of the problem symptom. See BODY ECU NO. 1 PROBLEM SYMPTOM INDEX  table. If the results are not OK, go to the next step.
  2. Check the taillight relay. See FOG LIGHT, HORN & TAILLIGHT CONTROL RELAY under RELAYS under COMPONENT TESTS in STEERING COLUMN SWITCHES. If the results are OK, go to the next step. If the results are not OK, replace the taillight relay.
  3. Check for short to power, short to ground and continuity in the wiring harness and connector between the taillight relay and body ECU No. 2, battery and taillight relay. If the results are OK, perform the next test procedure of the problem symptom. See BODY ECU NO. 1 PROBLEM SYMPTOM INDEX  table. If the results are not OK, repair or replace the wiring harness or connector.
Fig 1: Taillight Relay Circuit Wiring Diagram
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