For a complete wiring diagram Refer to Section 8WThe EGR Air Flow Control Valve is a two-wire electrically operated throttle valve motor used to assist the EGR system function by creating a vacuum in the intake system to draw exhaust gas into the intake manifold. The Solenoid receives 12 volts from the ECM/ASD relay and a pulse-width modulated ground signal from the ECM. With the solenoid de-energized (off) the throttle valve is in the open (full flow) position. When the ECM energizes (grounds) the throttle motor, the throttle valve closes creating a low pressure (vacuum) in the intake system. This low pressure effect helps draw exhaust gases from the EGR Valve into the intake system.When Monitored:With the ignition on and the ECM EGR Air Flow Control Valve command off.Set Condition:The ECM detects an open EGR Air Flow Control Valve Control circuit for 0.5 second.Possible CausesINTERMITTENT CONDITION(K344) ASD RELAY OUTPUT CIRCUIT OPEN(K54) EGR AIR FLOW CONTROL VALVE CONTROL CIRCUIT SHORTED TO GROUND(K54) EGR AIR FLOW CONTROL VALVE CONTROL CIRCUIT OPENEGR AIR FLOW CONTROL VALVEENGINE CONTROL MODULE1. CHECK FOR ACTIVE DTCIf the ECM detects and stores a DTC, the ECM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed.Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.Turn the ignition on.With the scan tool, erase ECM DTCs.Perform several ignition cycles, turning the ignition off for at least 10 seconds between each ignition cycle.Monitor the scan tool for ECM DTCs.Did this DTC set again?YesGo To 2NoRefer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.(Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)2. CHECKING FOR OTHER DTCSAn open ECM power supply to the ECM will cause multiple DTC's including this DTC to set.Check the ECM for other DTC's. If other DTC's are set with this DTC refer to the symptom list and perform the CHECKING THE ECM POWER AND GROUND CIRCUITS test before continuing.If the ECM power and ground circuits are functioning properly continue with this test.YesGo To 33. (K344) ECM RELAY OUTPUT CKT OPEN

Turn the ignition off.Disconnect the EGR Air Flow Control Valve harness connector.Turn the ignition on.Using a 12-volt test light connected to ground, check the (K344) ECM Relay Output circuit at the EGR Air Flow Control Valve harness connector.Does the test light illuminate brightly?YesGo To 4NoRepair the (K344) ECM Relay Output circuit for an open.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)4. (K54) EGR AIR FLOW CONTROL VALVE CONTROL CIRCUIT SHORTED TO GROUND

Turn the ignition off.Disconnect the EGR Air Flow Control Valve harness connector.Disconnect the ECM harness connectors.Measure the resistance between ground and the (K54) EGR Air Flow Control Valve Control circuit at the EGR Air Flow Control Valve harness connector.Is the resistance above 1000 ohms?YesGo To 5NoRepair the (K54) EGR Air Flow Control Valve Control circuit for a short to ground.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)5. (K54) EGR AIR FLOW CONTROL VALVE CONTROL CIRCUIT OPEN

Measure the resistance of the (K54) EGR Air Flow Control Valve Control circuit between the EGR Air Flow Control Valve harness connector and the ECM C1 harness connector.Is the resistance below 10.0 ohms?YesGo To 6NoRepair the (K54) EGR Air Flow Control Valve Control circuit for an open.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)6. EGR AIR FLOW CONTROL VALVEInstall a substitute EGR Air Flow Control Valve in place of the vehicle's EGR Air Flow Control Valve.Ensure the ECM and EGR Air Flow Control Valve harness connectors are connected.Turn the ignition on.With the scan tool, check for this DTC to set again.Did this DTC set again?YesReplace and program the Engine Control Module in accordance with the Service Information.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoReplace the EGR Air Flow Control Valve.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)