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Headlight Control Relay Circuit

NOTE: Verify normal headlight operation before performing this test.
  1. Turn ignition off. Disconnect anti-theft ECU connectors T5 and T6. Turn ignition on. Using a voltmeter, measure voltage between ECU connector T5 terminal No. 1 (Red/Blue wire) and body ground. See WIRING DIAGRAMS . If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair or replace wire harness and connectors between headlight control relay and anti-theft ECU.
  2. Check anti-theft ECU pin voltages. See ANTI-THEFT ECU PIN VOLTAGE TESTS  under COMPONENT TESTS. Replace components as necessary and retest system operation.