KOER Self-Test

Deactivate self-test by removing and reconnecting jumper wire or by procedure specified by test equipment in use. Start and run engine for 2 minutes at 2000 RPM to warm-up HEGO sensor. Turn engine off and wait 10 seconds. Activate KOER Self-Test by using a jumper wire or appropriate procedure for test equipment being used. Start engine. Record all service codes displayed. Check the following items:

• If engine starts and stalls, or stalls during self-test, go to TEST S, step 1).
• If vehicle is equipped with a Brake On/Off (BOO) switch, the brake pedal MUST be depressed and released AFTER the ID code portion of test.
• On vehicles equipped with Power Steering Pressure Switch (PSPS), the steering wheel must be turned at least one-half turn and released within 1-2 seconds after the ID code portion of test.
• On vehicles equipped with E4OD transmissions, the Overdrive Cancel Switch (OCS) MUST be cycled after the ID code portion of the test.
• When the Dynamic Response Code appears, perform a brief Wide Open Throttle (WOT). DO NOT perform a WOT unless requested.
• If Code 98 is displayed, it indicates EEC-IV system is operating in Failure Management Effects Mode (FMEM). Vehicle DID NOT pass KOEO Self-Test. Vehicle cannot be diagnosed while in FMEM mode, go to Code 98 reference in Continuous Memory Code reference chart.
• If a Code 11 (pass code) is received during KOER Self-Test, service Continuous Memory Codes which were received during KOEO SELF-TEST. Refer to the Continuous Memory Code reference chart.
• If a Code 11 (pass code) was received during the Continuous Memory Code portion of the KOEO Self-Test (Code 11-1-11), and no driveability symptoms are present, EEC-IV testing is complete. If driveability symptoms are still present, go to H - "Engine Type" TESTS W/O CODES article in this section.
• If KOER codes are present, refer to code reference charts. If system will not output codes, go to TEST QA, step 1).