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Home >> Ford >> 1991 >> Bronco 4.9 Y, Standard, M5OD-R2 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 4.9L >> Quick Test >> KOEO Self-Test
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KOEO Self-Test

Start engine and allow to idle until vehicle reaches operating temperature. If engine does not start or stalls after starting, continue KOEO SELF-TEST. DO NOT depress throttle on gasoline-engine vehicles. Turn ignition off and wait 10 seconds. Activate self-test procedure by using a jumper wire or appropriate test equipment. Turn ignition on, leaving engine off. Record all KOEO and Continuous Memory Codes.

If a Code 11 or 111 (pass code) is not received in the KOEO portion of test, service the KOEO codes. See appropriate chart under CODE-TO-TEST MENU(S). If the ECA will not output codes, go to TEST QA, step 1). If codes are received, check the following procedures: