FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Engine Controls Except For California




DTC 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 lights up.







DTC Confirmation Procedure

NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8 V at idle.
1.Start engine and let it idle for 1 second.
2.Check DTC.
3.If DTC is detected, go to .


Wiring Diagram






Specification data are reference values and are measured between each terminal and ground.

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.







Diagnosis Procedure


1. CHECK GROUND CONNECTIONS

1.Turn ignition switch OFF.





2.Loosen and retighten ground screws on the body.
Except For California.
-White arrow indicates : Vehicle front
-Body ground (1)
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 (1) harness connector.
2.Turn ignition switch ON.





3.Check voltage between APP sensor terminal 4 and ground with
CONSULT or tester.
Voltage: Approximately 5 V
OK or NG
OK- GO TO 8.
NG- GO TO 3.

3. CHECK SENSOR POWER SUPPLY CIRCUITS

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





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

4. CHECK CAMSHAFT POSITION SENSOR (PHASE)

Engine Controls Except For California.
OK or NG
OK- GO TO 5.
NG- Replace camshaft position sensor (PHASE).

5. CHECK THROTTLE POSITION SENSOR

Engine Controls Except For California.
OK or NG
OK- GO TO 7.
NG- GO TO 6.

6. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

Replace the electric throttle control actuator.
-INSPECTION END

7. CHECK APP SENSOR

Engine Controls Except For California.
OK or NG
OK- GO TO 9.
NG- GO TO 8.

8. REPLACE ACCELERATOR PEDAL ASSEMBLY

Replace accelerator pedal assembly.
-INSPECTION END

9. CHECK INTERMITTENT INCIDENT

Refer to Trouble Diagnosis For Intermittent Incident.
-INSPECTION END