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Home >> Ford >> 1989 >> Tempo Base >> Repair and Diagnosis >> Engine Performance >> System >> 2.3L CEC Tests W/Codes >> Quick Test >> Key On Engine Running (KOER) Self-Test >> Test Procedure
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Test Procedure

NOTE: This test procedure has been revised due to Ford Technical Service Bulletin 89-18A-10.
  1. Deactivate Self-Test by disconnecting STI jumper wire. Start and run engine at 2000 RPM for 2 minutes to warm up HEGO sensor. Turn engine off and wait 10 seconds
  2. Activate "Self-Test". See KEY ON ENGINE OFF (KOEO) SELF-TEST  .
  3. Start engine. The engine ID code will be displayed. On vehicles equipped with Brake On/Off switch (BOO), the brake pedal MUST be depressed and released AFTER the ID code (within 1-2 seconds). On vehicles equipped with Power Steering Pressure Switch (PSPS), the steering wheel MUST be turned one-half turn and released AFTER the ID code. On vehicles equipped with an Overdrive Cancel Switch (OCS) the switch must be cycled AFTER the ID code.
    4. NOTE: DO NOT depress throttle during test unless a Dynamic Response code occurs.
  4. If a Dynamic Response code occurs, briefly depress accelerator pedal to Wide Open Throttle (WOT). A Dynamic Response code is a Code 1 or 10 displayed after the Engine ID code and before the Engine Running codes. DO NOT depress throttle during test unless a Dynamic Response code occurs. The KOER Self-Test service codes will then be displayed. Observe and record all codes.
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