Headlight Control Relay Circuit

Ensure normal operation of headlights and taillights before proceeding with test. Turn ignition switch to OFF position and disconnect ATS ECU connectors. Ensure battery voltage exists between ground and ATS ECU connector "B" terminal No. 5 (Red/White wire). If battery voltage does not exist, repair open or short in harness or connectors between headlight control relay and ATS ECU. If battery voltage exists, check ATS ECU. See PIN VOLTAGE TESTS . If found to be defective, replace ATS ECU and retest system.