Description
ECM supplies a voltage of 5 V to some of the sensors systematically divided into 2 groups, respectively.
Accordingly, when a short circuit develops in a sensor power source, a malfunction may occur simultaneously in the sensors belonging to the same group as the short-circuited sensor.
Sensor power supply 1
NOTE: If sensor power supply 1 circuit is malfunctioning, DTC P0643 is displayed.
Sensor power supply 2
DTC Description
DTC DETECTION LOGIC
DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
P0643 | SENSOR POWER/CIRC (Sensor reference voltage ″A″ circuit high) | ECM detects that the voltage of sensor power supply 1 is excessively low or high. |
POSSIBLE CAUSE
FAIL-SAFE
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx.
5 degrees) by the return spring.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
Is DTC detected? YES >> Refer to EC-380, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK GROUND CONNECTION
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair or replace ground connection.
2.CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT
Is the inspection result normal? YES >> GO TO 5.
NO >> GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUITS
Check harness for short to power and short to ground, between the following terminals.
Is the inspection result normal? YES >> GO TO 4.
NO >> Repair short to ground or short to power in harness or connectors.
4.CHECK COMPONENTS
Check the following.
Is the inspection result normal? YES >> GO TO 5.
NO >> Repair or replace malfunctioning component.
5.CHECK APP SENSOR
Refer to EC-442, "Component Inspection".
Is the inspection result normal? YES >> GO TO 6.
NO >> Replace accelerator pedal assembly. Refer to ACC-3, "Removal and Installation".
6.CHECK INTERMITTENT INCIDENT
Refer to GI-41, "Intermittent Incident".
>> INSPECTION END
Compression pressure
CHECKING COMPRESSION PRESSURE
Warm up the engine to full operating temperature.
Release the fuel pressure. Refer to EC-144, "Work Procedure".
Remove the ignition coil and spark plug from each cylinder. Refer
to EM-36, "Removal and Installation"
and ...
Rapid air pressure loss
Rapid air pressure loss or a “blow-out” can occur
if the tire is punctured or is damaged due to
hitting a curb or pothole. Rapid air pressure loss
can also be caused by driving on under-inflated
tires.
Rapid air pressure loss can affect the handling
and stability of the vehicle, especial ...
Basic inspection
DIAGNOSIS AND REPAIR WORKFLOW
Work Flow
DETAILED FLOW
1.COLLECT THE INFORMATION FROM THE CUSTOMER
Get the detailed information from the customer about the symptom (the
condition and the environment when
the incident/malfunction occurred) using the diagnosis worksheet.
>> GO TO 2.
2. ...