P0643

P0643 Sensor Power Supply

On Board Diagnosis Logic

This self-diagnosis has the one trip detection logic.





Fail-Safe Mode

When the malfunction is detected, ECM enters fail-safe mode and the MIL illuminates.






DTC Confirmation Procedure

NOTE:

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

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 10 V at idle.
1) Start engine and let it idle for 1 second.
2) Check 1st trip DTC.
3) If DTC is detected, go to "Diagnosis Procedure".

Diagnosis Procedure

1. CHECK GROUND CONNECTIONS

1 Turn ignition switch OFF.
2 Loosen and retighten three ground three screws on the body. Refer to [Power Supply and Ground Circuit Check] Power Supply and Ground Circuit Check.






OK or NG
OK
GO TO 2.
NG
Repair or replace ground connections.

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 voltage between APP sensor terminal 2 and ground with SDT or tester.











OK or NG
OK
GO TO 5.
NG
GO TO 3.

3. CHECK SENSOR POWER SUPPLY CIRCUITS

Check harness for short to power and short to ground, between the following terminals.
[P0451 EVAP Control System Pressure Sensor] [1][2]Electrical Diagrams





OK or NG
OK
GO TO 4.
NG
Repair short to ground or short to power in harness or connectors.

4. CHECK COMPONENTS

Check the following.
- EVAP control system pressure sensor (Refer to P0451.)
- Refrigerant pressure sensor (Refer to [Refrigerant Pressure Sensor Circuit Check] Testing and Inspection.)
- Battery current sensor (Refer to [P1550 Battery Current Sensor] P1550.)
- Power steering pressure sensor (Refer to [P0550 PSP Sensor] P0550.)

OK or NG
OK
GO TO 5.
NG
Replace malfunctioning component.

5. CHECK APP SENSOR

Refer to [P2122, P2123 APP Sensor] P2122.

OK or NG
OK
GO TO 7.
NG
GO TO 6.

6. REPLACE ACCELERATOR PEDAL ASSEMBLY

1 Replace accelerator pedal assembly. Refer to [Accelerator Control System: Component] Component.
2 Perform [Accelerator Pedal Released Position Learning] Testing and Inspection.
3 Perform [Throttle Valve Closed Position Learning] Throttle Valve Closed Position Learning.
4 Perform [Idle Air Volume Learning] Idle Air Volume Learning.


INSPECTION END

7. CHECK INTERMITTENT INCIDENT

Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.


INSPECTION END