Key On Engine Off (KOEO) Injector Electrical Self-Test (Click Test)
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Key On Engine OFF (KOEO) injector electrical self-test (click test) is a functional test of the FICM performed on demand with the key on and the engine off. This test determines if the injector circuits and solenoids are electrically operating without fault. All injectors will click (audible feedback of the injector solenoids energizing the injector valves) together. Then each injector 1 through 8 is cycled approximately one second in sequence. This process is repeated three times during the entire test. If a fault is detected by the FICM, a CAN message is sent to the PCM. Corresponding fault DTCs are displayed at the end of the self-test.