Diagnosis Procedure

WARNING: This page is about a different car, the 2018 Nissan Titan XD. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR OTHER CURRENT DTC
1. Turn ignition switch ON.
2. Connect CONSULT and check "ENGINE" diagnostic trouble codes.
3. Check for other current DTCs on the CONSULT screen.
Are there any other current DTC detected?

YES

Refer to DTC Index .

NO

GO TO 2 .
CHECK FOR CURRENT DTC
1. Using CONSULT, check for "ENGINE" diagnostic trouble codes.
2. Check for P2457-00 being current DTCs on the CONSULT screen.
Is P2457-00 current DTC detected?

YES

GO TO 3 .

NO

Refer to Intermittent Incident .
CHECK THE ENGINE COOLANT MIXTURE
1. Turn ignition switch OFF.
2. Check the engine coolant mixture.
3. Check the freeze point of the engine coolant to be sure of a proper mixture.
NOTE: Incorrect coolant mixture will cause high EGR temperatures due to inefficient cooling.

Is engine coolant mixed correctly?

YES

GO TO 4 .

NO
- Drain the coolant and fill the cooling system with the proper mixture. Refer to Changing Engine Coolant .
- GO TO 13 .
CHECK THE ENGINE COOLANT LEVEL
Check for proper engine coolant level.

NOTE: Low engine coolant level can cause erratic coolant flow through the engine and EGR cooler, in turn, causing the EGR temperatures to rise.

Is Engine coolant level at proper level?

YES

GO TO 5 .

NO
- Check the cause of the improper coolant level. Refer to Coolant Loss - External .
- GO TO 13 .
CHECK THE EGR TEMPERATURE SENSOR ACCURACY
1. Remove the EGR temperature sensor from the EGR plumbing.
2. Turn ignition switch ON.
3. Using CONSULT, select ENGINE and check Data Monitor of EGR ORIFICE TEMP.
4. Compare the EGR temperature sensor reading to ambient air temperature.
NOTE: Allow the EGR temperature sensor enough time to cool down to ambient temperature before comparing the reading.

Is EGR temperature within 10°C (18°F) of ambient air temperature?

YES

GO TO 6 .

NO

GO TO 7 .
CHECK THE EGR COOLER FOR LEAKS OR FOULING
1. Turn ignition switch OFF.
2. Remove the EGR cooler.
3. Inspect and pressure test the EGR cooler.
Is EGR cooler pressure check within specification?

YES
- Clean the EGR cooler. Refer to Removal and Installation .
- GO TO 13 .
NO
- Replace the EGR cooler. Refer to Removal and Installation .
- GO TO 13 .
INSPECT THE EGR TEMPERATURE SENSOR AND ELECTRICAL CONNECTOR PINS
1. Turn ignition switch OFF.
2. Disconnect the EGR temperature sensor.
3. Inspect connector for the following:
  - Loose connector.
  - Corroded pins.
  - Bent or broken pins.
  - Pushed back or expanded pins.
  - Moisture in or on the connector.
  - Missing or damaged connector seals.
  - Dirt or debris on or in the connector pins.
  - Connector shell broken.
  - Wire insulation damage.
  - Damaged connector locking tab.
Is the inspection result normal?

YES

GO TO 8 .

NO
- Repair or replace error-detected parts.
- GO TO 13 .
CHECK THE CIRCUIT RESPONSE
1. Turn ignition switch ON.
2. Wait 30 seconds.
3. Using CONSULT, check for current ENGINE diagnostic trouble codes.
Is P040D-00 DTC current?

YES

GO TO 9 .

NO

GO TO 10 .
CHECK THE CIRCUIT RESPONSE
1. Turn ignition switch OFF.
2. Connect a jumper wire between the EGR temperature sensor connector F142 signal terminal 154 and return terminal 170.
3. Turn ignition switch ON.
4. Wait 30 seconds.
5. Using CONSULT, check for current ENGINE diagnostic trouble codes.
Is P040C-00 DTC current?

YES
- A malfunctioning EGR temperature sensor has been detected. Replace the EGR temperature sensor. Refer to Removal and Installation .
- GO TO 13 .
NO

GO TO 10 .
INSPECT ECM AND ELECTRICAL CONNECTOR PINS
1. Turn ignition switch OFF.
2. Disconnect the jumper wire.
3. Disconnect the ECM connector F101.
4. Inspect connectors for the following:
  - Loose connector.
  - Corroded pins.
  - Bent or broken pins.
  - Pushed back or expanded pins.
  - Moisture in or on the connector.
  - Missing or damaged connector seals.
  - Dirt or debris on or in the connector pins.
  - Connector shell broken.
  - Wire insulation damage.
  - Damaged connector locking tab.
Is the inspection result normal?

YES

GO TO 11 .

NO
- Repair or replace error-detected parts.
- GO TO 13 .
CHECK THE CIRCUIT RESPONSE
1. Turn ignition switch ON.
2. Wait 30 seconds.
3. Using CONSULT, check for current "ENGINE" diagnostic trouble codes.
Is P040D-00 DTC current?

YES

GO TO 12 .

NO
- Replace the ECM. Refer to Removal and Installation .
- GO TO 13 .
CHECK THE ECM RESPONSE
CAUTION:
When probing or jumping between connector pins or terminals:
- Always use extreme care or connector damage could result. Do not bend or damage connector pins and terminals. Damaged connectors, pins or terminals could result in additional issues or difficult-to-diagnose intermittent incidents.
- Do not probe or short unintended circuits or component and/or control module damage could result.
1. Turn ignition switch OFF.
2. Connect a jumper wire between ECM connector F101 pins 154 and 170.
3. Turn ignition switch ON.
4. Wait for 30 seconds.
5. Using CONSULT, check for current "ENGINE" diagnostic trouble codes.
Is P040C-00 DTC current?

YES

GO TO 13 .

NO
- Replace the ECM. Refer to Removal and Installation .
- GO TO 13 .
ERASE CURRENT DTC
1. Turn ignition switch OFF.
2. Disconnect jumper wire.
3. Connect all harness components and connectors.
4. Turn ignition switch ON.
5. Using CONSULT, erase "ENGINE" diagnostic trouble codes.
6. Operate the engine within the "Conditions for setting the DTC".
7. Using CONSULT, check for "ENGINE" diagnostic trouble codes.
Is P2457-00 DTC current?

YES

Return to Diagnosis Procedure. Refer to DTC Description .

NO

Repair complete.