DTC P0406: Exhaust Gas RECIRCULATION (EGR) Sensor A Circuit High

2011 Mercury Mariner Premier, 2.5 7, AWDSECTION DTC P0406: Exhaust Gas RECIRCULATION (EGR) Sensor A Circuit High
P0406 - EXHAUST GAS RECIRCULATION (EGR) SENSOR A CIRCUIT HIGH

Description:  The EGR monitor checks the EGR sensor signal to the powertrain control module (PCM) for high voltage. The test fails when the average voltage to the PCM exceeds the maximum calibrated value.
Possible Causes: 
  • Differential pressure feedback EGR circuit open
  • VREF circuit short to voltage
  • Damaged differential pressure feedback EGR sensor
  • Differential pressure feedback EGR circuit short to voltage
  • SIGRTN circuit open
Diagnostic Aids:  A DPFEGR PID reading greater than 4.5 volts with the ignition ON, engine OFF or running indicates a hard fault.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Crown Victoria,
E-Series,
F-Series Super
Duty 6.8L,
Grand Marquis,
Mustang 5.4L,
Town Car
GO to PINPOINT TEST HH .
All others GO to PINPOINT TEST HE .
RENDER: 1.0x

NO RELATED

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