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Home >> Ford >> 1989 >> Probe GL, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> 2.2L Systems/Tests W/Codes >> Diagnostic Routines >> Key On Engine Off (KOEO) Self-Test >> Test Procedure
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Test Procedure

  1. Turn ignition switch to "OFF" position. Ensure all procedures of PREPARATION & EQUIPMENT HOOK-UP have been followed. Engine should be at normal operating temperature.
  2. Turn ignition on. If using an analog VOM or the "Check Engine" (MIL) light, disconnect and reconnect the jumper wire from Self-Test Input (STI) pigtail to ground. Record displayed codes. Erase codes and repeat test procedure to ensure all codes are currently valid. Service only those codes which appear during the re-test. Refer to SERVICE CODE TO CIRCUIT TEST REFERENCE CHART to find the appropriate CIRCUIT TEST.
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