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Home >> Ford >> 1986 >> Bronco II RWD, Standard >> Repair and Diagnosis >> Engine Performance >> System >> 2.9L EFI EEC IV Testing >> Quick Tests >> Key On/Engine Running Self-Test >> Code Output
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Code Output

  1. Deactivate SELF-TEST (disconnect jumper wire). Start and run engine at 2000 RPM for 2 minutes to warm up EGO sensor. Turn engine off and wait 10 seconds. Insert jumper to activate SELF-TEST. DO NOT  depress throttle during test unless a Dynamic Response code occurs.
  2. Start engine. The engine ID code will be displayed. Run test. If Dynamic Response code 1 (10 with STAR tester) occurs, briefly accelerate engine to wide open throttle (WOT). The KEY ON/ENGINE RUNNING SELF-TEST  codes will then be displayed. Observe and record all codes.
NOTE: The Engine ID code is 1/2 the number of cylinders (a 2 equals a 4 cylinder engine). STAR tester adds a zero to all single digit readings. A "20" on STAR tester equals a 4 cylinder engine. Some vehicles do not require a brief WOT, they will not display a 1 (10).
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