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Home >> Ford >> 1989 >> Bronco II 4WD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> 2.9L CEC Tests W/Codes >> Quick Test >> Key On Engine Running (KOER) Self-Test >> Description
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Key On Engine Running (KOER) Self-Test: Description

This test checks engine sensors under actual operating conditions and at operating temperature. The ECA operates and tests actuators and sensors during this test. A number of special test procedures may be requested by the ECA during this test, depending on vehicle equipment. These tests allow the ECA to test the following sensors.