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Service Code Sequence


There are three parts to the self-test, which are the Key-ON/Engine-OFF, Computed Ignition Timing Check and Engine Running.
Key-ON/Engine-OFF--Checks the system inputs for faults (malfunctions) that occur during the self-test procedure, and intermittent faults (malfunctions) that occurred prior to the self-test procedure.
Computed Ignition Timing Check--Checks the ECA's ability to advance or retard ignition timing.
Engine Running--Checks system outputs for faults (malfunctions) only.
During the Key-ON/Engine-OFF part of the self-test, the following should be obtained or noted on the STAR tester:
1. Fast codes--LED light flickers.
2. ON-Demand codes--Hard faults (malfunctions).
3. Separator code--Numeral 10.
4. Memory codes--Intermittent faults (malfunctions).
During the Engine Running portion of the self-test, the following should be obtained or noted on the STAR tester:
1. Engine identification code--Numerals 20, 30 or 40.
2. Dynamic response code--Numeral 10.
3. Fast codes--LED light flickers.
4. ON-Demand codes--Hard faults (malfunctions).