DTC P1408: Exhaust Gas RECIRCULATION (EGR) Flow Out Of Self-Test Range (Non-Mil)

2006 Lincoln ZephyrSECTION DTC P1408: Exhaust Gas RECIRCULATION (EGR) Flow Out Of Self-Test Range (Non-Mil)
P1408 - EXHAUST GAS RECIRCULATION (EGR) FLOW OUT OF SELF-TEST RANGE (NON-MIL)

Description:  This test is carried out during the key on engine running (KOER) on-demand self-test only. The EGR system is commanded on at a fixed engine speed. The test does not pass and the DTC is set when the measured EGR flow falls above or below the required calibration.
Possible Causes: 
  • For electric EGR (EEGR) system, see possible causes for DTC P0400.
  • For vacuum activated systems, see the possible causes for DTC P0401.
Diagnostic Aids:  For EEGR, use the output state control function of the diagnostic tool and monitor the manifold absolute pressure (MAP) PID and the EEGR PID (EGRMDSD) while commanding the EEGR on. If EGR is introduced into the engine at idle, the RPM will drop or stall out. For vacuum systems see diagnostic aids for P0401.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Vehicles With an Electric EGR (EEGR) - GO to Pinpoint Test KD . -
Vehicles with an EGR system module (ESM) - GO to Pinpoint Test HH . -
All others - GO to Pinpoint Test HE . -
RENDER: 1.0x

NO RELATED

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