Circuit DescriptionThe ECM uses diagnostic software to verify injector operation. During selected conditions, each injector is fired. The fueling quantity and timing are then compared to a specified threshold.

Component LocationThe engine harness connects the ECM to the pass-through connector(s) that are located in the rocker housing. Internal injector harnesses are located under the valve cover and connect the injectors to the engine harness at the pass-through connector(s).

Conditions for Running the DiagnosticsThis diagnostic runs periodically during engine operation.

Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected a fueling timing or quantity error for the specified injector.

Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.Conditions for Clearing the Fault CodeIt is necessary to use the “Reset All Faults” command in INSITE™ electronic service tool to clear this fault and extinguish the amber CHECK ENGINE lamp and/or Malfunction Indicator Lamp (MIL).

Shop TalkThis fault code is intended to identify fueling quantity and timing issues.

Possible Cause:1) Cylinder number 3 Fuel injector failure2) ECM calibration