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Home >> Ford >> 1990 >> Bronco II 4WD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> EEC-IV Functional Tests >> Continuous Monitor Mode (Wiggle Test) >> Engine Running (KOER) Wiggle Test Procedure
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Engine Running (KOER) Wiggle Test Procedure

Wiggle Test is entered by starting, stopping, and restarting a regular KOER self-test.

Connect test equipment. In this article, see STEP 2.0: VEHICLE PREP & EQUIPMENT HOOKUP . Wait 10 seconds with the ignition key Off. Start the engine. Activate self-test. See STEP 5.0: PERFORM ENGINE RUNNING (KOER) SELF-TEST .

Wait 10 seconds, deactivate, and then reactivate self-test. DO NOT  shut the engine off.

You are now in Continuous Monitor (Wiggle Test) mode. Tap, move, and wiggle the suspected sensor and/or harness area.

If a fault is detected, a service code will be stored in memory. This will be indicated as follows, depending on the type of equipment being used:

Record or retrieve code and perform test indicated in: