Diagnosis Procedure

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

CHECK DTC PRIORITY
If DTC P0122 or P0123 is displayed with another DTC P0643, first perform the trouble diagnosis for DTC P0643.

Is applicable DTC detected?

YES

Perform diagnosis of applicable. Refer to DTC Description .

NO

GO TO 2.

CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY

Disconnect electric throttle control actuator harness connector.
Turn ignition switch ON.

Check the voltage between electric throttle control actuator harness connector and ground.

+		-	Voltage
Electric throttle control actuator
Connector	Terminal
F57	5	Ground	Approx. 5 V

Is the inspection result normal?

YES

GO TO 4.

GO TO 3.

CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT

Turn ignition switch OFF.
Disconnect ECM harness connector.

Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

Electric throttle control actuator		ECM		Continuity
Connector	Terminal	Connector	Terminal	Continuity
F57	5	F14	98	Existed

Is the inspection result normal?

YES

INSPECTION END

Repair or replace error-detected parts.

CHECK THROTTLE POSITION SENSOR 2 GROUND CIRCUIT

Turn ignition switch OFF.
Disconnect ECM harness connector.

Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

Electric throttle control actuator		ECM		Continuity
Connector	Terminal	Connector	Terminal	Continuity
F57	4	F14	75	Existed

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

GO TO 5.

Repair open circuit, short to ground or short to power in harness or connectors.

CHECK THROTTLE POSITION SENSOR 2 INPUT SIGNAL CIRCUIT

Check the continuity between electric throttle control actuator harness connector and ECM harness connector.

Electric throttle control actuator		ECM		Continuity
Connector	Terminal	Connector	Terminal	Continuity
F57	3	F14	72	Existed

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

GO TO 6.

Repair open circuit, short to ground or short to power in harness or connectors.

CHECK THROTTLE POSITION SENSOR
Check throttle position sensor. Refer to Component Inspection .

Is the inspection result normal?

YES

INSPECTION END

NO

Replace electric throttle control actuator. Refer to Removal and Installation .