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 DTC PRIORITY
1. Turn ignition switch ON.
2. Connect CONSULT and check for ENGINE diagnostic trouble codes.
3. Check for DTC P0254-00 being current on the CONSULT screen.
Is DTC P0254-00 detected as current?

YES

GO TO 2 .

NO

Refer to Intermittent Incident .
INSPECT FUEL PUMP ACTUATOR AND CONNECTOR PINS
1. Turn ignition switch OFF.
2. Disconnect fuel pump actuator harness connector F123.
3. Inspect the harness connector and fuel pump actuator pins 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 3 .

NO

Repair or replace error-detected parts.
CHECK THE CIRCUIT RESPONSE
1. Turn ignition switch OFF.
2. Disconnect fuel pump actuator harness connector F123.
3. Connect a jumper wire between fuel pump actuator harness connector F123 terminal 1 and 2.
4. Turn ignition switch ON and wait seconds.
5. Connect CONSULT and check for current ENGINE diagnostic trouble codes.
Did DTC P0253-00 become current and P0254-00 become past?

YES

GO TO 4 .

NO

GO TO 5 .
CHECK DTCS AND FUEL PUMP ACTUATOR CONDITION
1. Turn ignition switch OFF.
2. Connect fuel pump actuator harness connector F123.
3. Turn ignition switch ON and wait 30 seconds.
4. Connect CONSULT and check for current ENGINE diagnostic trouble codes.
Did DTC P0254-00 become current?

YES

Replace fuel pump actuator. Refer to Removal and Installation .

NO

The removal and installation of the connector corrected the malfunction.
INSPECT ECM AND HARNESS CONNECTOR PINS
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector F101.
3. Inspect the ECM connector pins 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 6 .

NO

Repair or replace error-detected parts.
CHECK THE ECM RESPONSE
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector F101.
3. Connect a jumper wire between the fuel pump actuator signal circuit pin 118 and battery voltage at the ECM harness connector F101.
4. Turn ignition switch ON and wait 30 seconds.
Did P0253-00 DTC become current and P0254-00 become past?

YES

GO TO 7 .

NO

Replace ECM. Refer to Removal and Installation .

CHECK FOR AN OPEN CIRCUIT IN THE ENGINE HARNESS

Turn ignition switch OFF.
Disconnect the jumper wire.

Measure the resistance between the ECM harness connector F101 terminal 118 and the fuel pressure relief valve harness connector F123 terminal 2.

ECM		Fuel pump actuator		Resistance
Connector	Terminal	Connector	Terminal	Resistance
F101	118	F123	2	< 10 Ω

Is resistance less than 10 ohms?

YES

GO TO 8 .

Repair or replace the engine harness for an open.

CHECK FOR A PIN-TO-PIN SHORT CIRCUIT IN THE ENGINE HARNESS

Turn ignition switch OFF.
Disconnect the ECM harness connector F101.
Disconnect the fuel pump actuator harness connector F123.

Measure the resistance between the ECM harness connector terminal 118 and all other terminals in the ECM harness connector F101.

ECM		ECM		Resistance
Connector	Terminal	Connector	Terminal	Resistance
F101	118	F101	All	> 100k Ω

Is resistance greater than 100k ohms?

YES

GO TO 9 .

Repair or replace the engine harness for a short.

CHECK THE CIRCUIT RESPONSE
1. Turn ignition switch OFF.
2. Connect all components.
3. Turn ignition switch ON and wait 30 seconds.
4. Connect CONSULT and check for current ENGINE diagnostic trouble codes.
Did DTC P0254-00 become past?

YES

The removal and installation of the connector corrected the fault.

NO

Troubleshooting procedures need to be repeated from the beginning. A failure mode should have been be detected. Refer to DTC Description .