Key-On Engine Running (KOER) Self-test

This test checks sensors under actual operating conditions and at normal operating temperature. Any faults must be present at time of test to be detected.

NOTE: If engine will not start, perform Test A.

Connect jumper wire or STAR tester to activate test. This test will display an Engine ID code, a Dynamic Response code and an On Demand Service code. After a Dynamic Response code (single digit) is received, quickly press and release accelerator once only.

Deactivate the self-test. Start and run engine at more than 2000 RPM for 2 minutes. Turn engine off and wait 10 seconds. Activate self-test. Start engine. Test will proceed with Engine ID code, Dynamic Response code and Engine Running On Demand Service codes. If a 10 or 1 pulse occurs during Dynamic Response code, open throttle wide open momentarily. Record codes and proceed as follows:

KEY ON ENGINE RUNNING (KOER) SELF-TEST RESULTS

On Demand Codes

Proceed to Test

⁽¹⁾ CONTINUOUS TEST

Any

See Code No. Below

None

Repeat self-test; then Test K

Test L

Test L, step 8)

Test F

Test E

Test H

Test D

Test G

Test I

Test M

Test N, step 8)

Test N, step 5)

Test H, step 14)

Test I, step 13)

Test O

⁽¹⁾	If drive problem still exists, go to Test U.

NOTE: If engine stalls while testing, proceed to Test K, step 10).