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Home >> Ford >> 1984 >> Bronco II Automatic >> Repair and Diagnosis >> Engine Performance >> System >> 2.8L EEC IV Testing >> Quick Test >> Key On-Engine Running Self-Test
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Key On-Engine Running Self-Test

This test checks sensors under actual operating conditions and at normal operating temperature. Any faults must be present at time of test to be detected.

NOTE: If engine will not start, perform TEST A  .

Connect jumper wire or STAR tester to activate test. This test will display an Engine ID code, a Dynamic Response code and an On Demand Service code. After a Dynamic Response code (single digit) is received, quickly press and release accelerator once only.

Deactivate the self-test. Start and run engine at more than 2000 RPM for 2 minutes. Turn engine off and wait 10 seconds. Activate self-test. Start engine. Test will proceed with Engine ID code, Dynamic Response code and Key On-Engine Running On Demand Service codes. If a 10 or 1 pulse occurs during Dynamic Response code, open throttle wide open momentarily. Record codes and proceed as follows:

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