Lincoln Navigator Manuals

Lincoln Navigator: Engine Emission Control - 3.5L EcoBoost (272kW/370PS) / Exhaust Gas Recirculation (EGR) System. Diagnosis and Testing

Lincoln Navigator 2018-2025 Workshop Manual / Engine / Engine Emission Control - 3.5L EcoBoost (272kW/370PS) / Exhaust Gas Recirculation (EGR) System. Diagnosis and Testing

Diagnostic Trouble Code (DTC) Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


Module DTC Description Action
PCM P0401:00 EGR 'A' Flow Insufficient Detected: No Sub Type Information GO to Pinpoint Test HE
PCM P0402:00 EGR 'A' Flow Excessive Detected: No Sub Type Information GO to Pinpoint Test HE
PCM P0404:00 EGR 'A' Control Circuit Range/Performance: No Sub Type Information GO to Pinpoint Test KD
PCM P0405:00 EGR Sensor 'A' Circuit Low: No Sub Type Information GO to Pinpoint Test KD
PCM P0406:00 EGR Sensor 'A' Circuit High: No Sub Type Information GO to Pinpoint Test KD
PCM P041B:00 EGR Temperature Sensor 'B' Circuit Range/Performance: No Sub Type Information GO to Pinpoint Test DS
PCM P041C:00 EGR Temperature Sensor 'B' Circuit Low: No Sub Type Information GO to Pinpoint Test DS
PCM P041D:00 EGR Temperature Sensor 'B' Circuit High: No Sub Type Information GO to Pinpoint Test DS
PCM P044C:00 EGR Sensor 'C' Circuit Low: No Sub Type Information GO to Pinpoint Test HE
PCM P044D:00 EGR Sensor 'C' Circuit High: No Sub Type Information GO to Pinpoint Test HE
PCM P0471:00 Exhaust Pressure Sensor 'A' Circuit Range/Performance: No Sub Type Information GO to Pinpoint Test DT
PCM P0472:00 Exhaust Pressure Sensor 'A' Circuit Low: No Sub Type Information GO to Pinpoint Test DT
PCM P0473:00 Exhaust Pressure Sensor 'A' Circuit High: No Sub Type Information GO to Pinpoint Test DT
PCM P04FA:00 EGR 'A' Control Temperature Too High: No Sub Type Information GO to Pinpoint Test KD
PCM P139A:00 EGR Sensor 'C' Hoses Reversed: No Sub Type Information GO to Pinpoint Test HE
PCM P139B:00 EGR Sensor 'C' Upstream Hose Off or Plugged: No Sub Type Information GO to Pinpoint Test HE
PCM P139C:00 EGR Sensor 'C' Downstream Hose Off or Plugged: No Sub Type Information GO to Pinpoint Test HE
PCM P1408:00 EGR Flow Out Of Self Test Range: No Sub Type Information GO to Pinpoint Test HE
PCM P2457:00 EGR Cooler 'A' Efficiency Below Threshold: No Sub Type Information GO to Pinpoint Test HE

Global Customer Symptom Code (GCSC) Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


Symptom Action
Start/Run/Move > Running > Failed Emissions Testing > Catalyst GO to Pinpoint Test DS
Start/Run/Move > Running > Failed Emissions Testing > Catalyst GO to Pinpoint Test DT
Start/Run/Move > Running > Failed Emissions Testing > Catalyst GO to Pinpoint Test HE
Start/Run/Move > Running > Failed Emissions Testing > Catalyst GO to Pinpoint Test KD
Driving Performance > Lack/Loss of Power > Acceleration > Always GO to Pinpoint Test HE
Driving Performance > Lack/Loss of Power > Acceleration > Always GO to Pinpoint Test KD
Driving Performance > Lack/Loss of Power > Cruise/ Steady Speed > Always GO to Pinpoint Test HE
Driving Performance > Lack/Loss of Power > Cruise/ Steady Speed > Always GO to Pinpoint Test KD
Driving Performance > Poor Fuel Economy > Combined > Loaded GO to Pinpoint Test HE
Driving Performance > Poor Fuel Economy > Combined > Loaded GO to Pinpoint Test KD

Pinpoint Tests


PINPOINT TEST DS: EXHAUST GAS RECIRCULATION TEMPERATURE (EGRT) SENSOR
Introduction

Normal Operation and Fault Conditions

Refer to the DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
PCM P041B:00 EGR Temperature Sensor 'B' Circuit Range/Performance: No Sub Type Information Sets when the PCM detects the EGRT bank 1, sensor 2 temperature is less than or greater than a calibrated limit for a specified amount of time. When the change in the EGRT bank 1, sensor 2 is less than or greater than a calibrated threshold, an increment counter advances for that drive cycle. Diagnose any ECT or IAT2 sensor related concerns before diagnosing this DTC .
PCM P041C:00 EGR Temperature Sensor 'B' Circuit Low: No Sub Type Information Sets when the PCM detects the EGRT bank 1, sensor 2 temperature is greater than a calibrated limit for a specified amount of time. When the change in the EGRT bank 1, sensor 2 is less than or greater than a calibrated threshold, an increment counter advances for that drive cycle.
PCM P041D:00 EGR Temperature Sensor 'B' Circuit High: No Sub Type Information Sets when the PCM detects the EGRT bank 1, sensor 2 temperature is less than a calibrated limit for a specified amount of time. When the EGRT bank 1, sensor 2 is greater than a calibrated threshold, an increment counter advances for that drive cycle.

Possible Sources

  • EGR cooler system concern
  • EGRT sensor circuitry concern
  • EGRT sensor
PINPOINT TEST DT: EXHAUST PRESSURE SENSOR
Introduction

Normal Operation and Fault Conditions

Refer to the DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
PCM P0471:00 Exhaust Pressure Sensor 'A' Circuit Range/Performance: No Sub Type Information Sets when the PCM detects the exhaust pressure sensor signal is not within a calibrated value. The exhaust pressure sensor reading should be greater than the BARO sensor reading by a calibrated threshold while the engine is running.
PCM P0472:00 Exhaust Pressure Sensor 'A' Circuit Low: No Sub Type Information Sets when the PCM detects the exhaust pressure sensor signal is less than the PCM self test minimum.
PCM P0473:00 Exhaust Pressure Sensor 'A' Circuit High: No Sub Type Information Sets when the PCM detects the exhaust pressure sensor signal is greater than the self test maximum.

Possible Sources

  • Exhaust pressure sensor circuitry concern
  • Exhaust pressure sensor (9J460)
  • PCM (12A650)
PINPOINT TEST HE: EXHAUST GAS RECIRCULATION (EGR) SYSTEMS
Introduction

Normal Operation and Fault Conditions

Refer to the DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
PCM P0401:00 EGR 'A' Flow Insufficient Detected: No Sub Type Information Sets when PCM detects the signal from the differential pressure feedback EGR sensor indicates that EGR flow is less than the desired minimum. The EGR system is monitored during steady state driving conditions while the EGR is commanded on.
PCM P0402:00 EGR 'A' Flow Excessive Detected: No Sub Type Information Sets when PCM detects the signal at idle is greater than at KOEO by a calibrated amount. The EGR system is monitored for undesired EGR flow during idle. The EGR monitor looks at the differential pressure feedback EGR signal at idle and compares it to the stored signal measured during KOEO. A DPFEGR PID reading that is greater at idle than during KOEO by 0.5 volt or a rough engine idle may indicate a concern.
PCM P044C:00 EGR Sensor 'C' Circuit Low: No Sub Type Information Sets when PCM detects the average voltage to the PCM drops to a voltage less than the minimum calibrated value. The EGR monitor checks the differential pressure feedback EGR sensor signal to the PCM for low voltage.
PCM P044D:00 EGR Sensor 'C' Circuit High: No Sub Type Information Sets when PCM detects the average voltage to the PCM exceeds the maximum calibrated value. The EGR monitor checks the differential pressure feedback EGR sensor signal to the PCM for high voltage.
PCM P139A:00 EGR Sensor 'C' Hoses Reversed: No Sub Type Information Sets when PCM detects the differential pressure indicated by the sensor exceeds a maximum threshold or falls below a minimum threshold. At idle, the EGR monitor commands the EGR valve closed and checks the differential pressure across the EGR tube orifice which should be zero to indicate the hoses are connected and not restricted. Look for signs of water or icing in the hose. Verify the hose connection and routing. Check the differential pressure feedback EGR sensor for correct mounting and function.
PCM P139B:00 EGR Sensor 'C' Upstream Hose Off or Plugged: No Sub Type Information Sets when PCM detects the differential pressure indicated by the sensor exceeds a maximum threshold or falls below a minimum threshold. At idle, the EGR monitor commands the EGR valve closed and checks the differential pressure across the EGR tube orifice which should be zero to indicate the hoses are connected and not restricted. Look for signs of water or icing in the hose. Verify the hose connection and routing. Check the differential pressure feedback EGR sensor for correct mounting and function.
PCM P139C:00 EGR Sensor 'C' Downstream Hose Off or Plugged: No Sub Type Information Sets when PCM detects the differential pressure indicated by the sensor exceeds a maximum threshold or falls below a minimum threshold. At idle, the EGR monitor commands the EGR valve closed and checks the differential pressure across the EGR tube orifice which should be zero to indicate the hoses are connected and not restricted. Look for signs of water or icing in the hose. Verify the hose connection and routing. Check the differential pressure feedback EGR sensor for correct mounting and function.
PCM P1408:00 EGR Flow Out Of Self Test Range: No Sub Type Information Sets when PCM detects the measured EGR flow falls above or below the required calibration. This test is carried out during the key ON, KOER on demand self test only. The EGR system is commanded on at a fixed engine speed. When using the output state control function of the scan tool and monitoring the MAP and the EGRMDSD PIDs, command the EGR on. If EGR is introduced into the engine at idle, the RPM drops or stalls out.
PCM P2457:00 EGR Cooler 'A' Efficiency Below Threshold: No Sub Type Information Sets when PCM detects the difference between the expected temperature of the exhaust gas and the actual EGRT bank 1, sensor 2 value is greater than a calibrated amount.

Possible Sources

  • Cooling system concern
  • Differential pressure feedback EGR circuitry concern
  • Differential pressure feedback EGR sensor hose
  • EGR cooler
  • EGR valve
  • Differential pressure feedback EGR sensor (9J460)
  • Orifice tube assembly (9D477)
  • PCM (12A650)
PINPOINT TEST KD: ELECTRIC EXHAUST GAS RECIRCULATION (EGR)
Introduction

Normal Operation and Fault Conditions

Refer to the DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
PCM P0404:00 EGR 'A' Control Circuit Range/Performance: No Sub Type Information Sets when the PCM detects the EGR valve is at a position other than commanded.
PCM P0405:00 EGR Sensor 'A' Circuit Low: No Sub Type Information Sets when the PCM detects the average voltage to the PCM drops to a voltage less than the minimum calibrated value. The EGR monitor checks the EGR valve position sensor signal to the PCM for low voltage.
PCM P0406:00 EGR Sensor 'A' Circuit High: No Sub Type Information Sets when the PCM detects the average voltage to the PCM exceeds the maximum calibrated value. The EGR monitor checks the EGR valve position sensor signal to the PCM for high voltage.
PCM P04FA:00 EGR 'A' Control Temperature Too High: No Sub Type Information Sets when the PCM detects the EGR valve position and speed of position is greater than a specified limit.

Possible Sources

  • EGR valve circuitry concern
  • MAP sensor
  • MAF sensor
  • EGR valve
  • PCM (12A650)

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    Symptom Chart(s)

    Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
    REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

    Symptom Chart - Differential

      Symptom Chart - Differential


    Condition Actions Axle overheating   GO to Pinpoint Test A Broken gear teeth on the ring gear or pinion   GO to Pi

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