DTC P0400: Exhaust Gas Recirculation (EGR) Flow Failure (Outside the Minimum or Maximum Limits)

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P0400 - EXHAUST GAS RECIRCULATION (EGR) FLOW FAILURE (OUTSIDE THE MINIMUM OR MAXIMUM LIMITS)

Description:	The electric EGR (EEGR) system is monitored once per drive cycle during steady state conditions above 77 km/h (48 mph). The test fails when a malfunction is detected by powertrain control module (PCM) calculations indicating the EGR flow is less or greater than expected.
Possible Causes:	EEGR valve stuck open or closed Connector to EEGR not seated EEGR motor winding circuits short or open No voltage to the EEGR Harness open or shorted to voltage or ground Vacuum signal to manifold absolute pressure (MAP) restricted or leaking Mass air flow (MAF) sensor signal erroneous Carbon build up in the EEGR valve seat area One or more sensors is not responding or is out of range
Diagnostic Aids:	All of the following sensors input data to the PCM for proper operation of the EEGR system: engine coolant temperature (ECT, crankshaft position (CKP), intake air temperature (IAT), MAF, throttle position (TP), MAP. Any DTC relating to these sensors must be resolved prior to addressing code P0400.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to KD: Electric Exhaust Gas Recirculation (EEGR) System STEP KD8.