Nissan Maxima Service and Repair Manual: P0643 sensor power supply

DTC Logic

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is more than 8 V at idle

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON.
2. Start engine and let it idle for 1 second.
3. Check DTC

Diagnosis Procedure

1.CHECK GROUND CONNECTION

1. Turn ignition switch OFF.
2. Check ground connection E9.

2.CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT

1. Disconnect accelerator pedal position (APP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between APP sensor harness connector and ground.

3.CHECK SENSOR POWER SUPPLY CIRCUIT

Check harness for short to power and short to ground, between the following terminals.

4.CHECK COMPONENTS

Check the following.

• Camshaft position sensor (PHASE) (Refer to EC-302, "Component Inspection".)
• EVT control position sensor (Refer to EC-402, "Component Inspection".)
• Battery current sensor (Refer to EC-415, "Component Inspection".)
• Power steering pressure sensor

5.CHECK TP SENSOR

6.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1. Replace electric throttle control actuator.

7.CHECK APP SENSOR

8.REPLACE ACCELERATOR PEDAL ASSEMBLY

1. Replace accelerator pedal assembly.

9.CHECK INTERMITTENT INCIDENT