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Home >> Ford >> 1997 >> Probe GTS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 2.5L >> Quick Test >> Key On Engine Running (KOER) Self-Test
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Key On Engine Running (KOER) Self-Test

  1. Ensure engine is warmed to normal operating temperature. Turn ignition switch to OFF position. Ensure test equipment is properly attached.
  2. If vehicle information has not already been entered into NGS tester, enter vehicle year, engine, model and any additional information requested by scan tool.
  3. To request KOER SELF-TEST enter the following into NGS tester:
    • Select DIAGNOSTIC DATA LINK.
    • Select PCM - POWERTRAIN CTRL MODULE.
    • Select DIAGNOSTIC TEST MODE.
    • Select KOER ON-DEMAND SELF-TEST.
    • Start engine and allow to idle (transmission in Neutral or Park).
    • Press START button to retrieve DTCs.
  4. At this point, scan tool should display all KOER DTCs. Write down codes in order displayed. If a communication problem exists between scan tool and PCM, see COMMUNICATION ERROR.
  5. If one or more DTCs were retrieved, refer to DIAGNOSTIC TROUBLE CODE (DTC) REFERENCE CHART under DIAGNOSTIC TROUBLE CODE (DTC) to find proper CIRCUIT TEST to perform. Service DTCs in order scan tool displayed them. If no DTCs or Code P1000 (system ready) were retrieved, proceed to SWITCH MONITOR TEST.
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