1988 Ford Bronco II 4WD, Standard, M5OD-R1FACTORY OEM SERVICE PROCEDURE

Quick Test: Notes

The QUICK TEST diagnostic procedure is a functional test of the EEC-IV system. It consists of 4 basic test steps. These basic steps must be carefully followed in sequence, otherwise misdiagnosis, or replacement of non-faulty components may result.

  • PREPARATION and EQUIPMENT HOOK-UP.
  • KEY ON ENGINE OFF (KOEO) SELF-TEST.
  • KEY ON ENGINE RUNNING (KOER) SELF-TEST.
  • CONTINUOUS SELF-TEST.
After all tests, servicing, or repairs have been completed, repeat QUICK TEST to ensure all EEC-IV systems work properly. The KOEO and KOER SELF-TESTS are intended to detect faults present at the time of testing, not intermittent faults. Intermittent faults are detected by CONTINUOUS SELF-TEST and stored in the ECA memory.

NOTE: Correct test results for system are dependent on the correct operation of several related non-EEC components and systems. All non-EEC problems should be corrected before attempting to diagnose the EEC system.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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