DTC P1408 - EGR Flow Out Of Self Test Range

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DTC DESCRIPTION P1408 - EGR FLOW OUT OF SELF TEST RANGE

For Vehicles With DPFEGR
Description:	This test is carried out during the key ON, engine running (KOER) on demand self test only. The exhaust gas recirculation (EGR) system is commanded on at a fixed engine speed. This DTC sets when the measured EGR flow falls above or below the required calibration.
Possible Causes:	VREF circuit open SIGRTN circuit open DPFE circuit open DPFE circuit short to voltage DPFE circuit short to ground The upstream hose is disconnected The upstream hose is restricted The downstream hose is disconnected The downstream hose is restricted The upstream hose and downstream hose are reversed Restricted or damaged EGR tube
Diagnostic Aids:
For Vehicles With An Electric EGR
Description:	This test is carried out during the key ON, engine running (KOER) on demand self test only. The exhaust gas recirculation (EGR) system is commanded on at a fixed engine speed. This DTC sets when the measured EGR flow falls above or below the required calibration.
Possible Causes:	EGR valve stuck open or closed EGR connector not seated correctly VPWR circuit open EGRMC circuit open EGRMC circuit short to voltage EGRMC circuit short to ground Vacuum signal to manifold absolute pressure (MAP) sensor restricted or leaking Mass airflow (MAF) sensor signal erroneous Carbon build up in the EGR valve seat area Damaged EGR valve
Diagnostic Aids:	Use the output state control function of the scan tool and monitor the MAP and the EGRMDSD PIDs while commanding the EGR on. If EGR is introduced into the engine at idle, the RPM drops or stalls out.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
Corsair, Escape/Kuga 2.0L, Escape/Kuga 2.5L, Explorer 2.3L, Explorer 3.3L, F-150 2.7L, F-150 3.3L, Nautilus 2.0L, Ranger 2.3L, Transit 3.5L TiVCT	GO to PINPOINT TEST HE .
Fusion 2.5L, Transit Connect 2.5L	GO to PINPOINT TEST KD .