P0451

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR





DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure 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.
- GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and wait at least 40 seconds.

NOTE:
Do not depress accelerator pedal even slightly.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Proceed to SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check that water is not inside connectors.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace harness connector.
2.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check the voltage between EVAP control system pressure sensor harness connector and ground.





Is the inspection result normal?
YES - GO TO 7.
NO - GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUIT
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.
- CKP sensor ( P0335.)
- Camshaft position sensor (bank 1) ( P0340.)
- Battery current sensor ( P1550.)
- EVAP control system pressure sensor ( SEE Component Inspection (EVAP Control System Pressure Sensor).)
- Refrigerant pressure sensor ( Testing and Inspection.)
Is the inspection result normal?
YES - GO TO 5.
NO - Replace malfunctioning component.
5.CHECK APP SENSOR
P2122.
Is the inspection result normal?
YES - GO TO 8.
NO - GO TO 6.
6.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Removal And Installation Without Distance Control Assist System(Without distance control assist system)
Removal And Installation With Distance Control Assist System (With distance control assist system).
- INSPECTION END
7.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
SEE Component Inspection (EVAP Control System Pressure Sensor).
Is the inspection result normal?
YES - GO TO 8.
NO - Replace EVAP control system pressure sensor.
8.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END




Component Inspection (EVAP Control System Pressure Sensor)
1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Turn ignition switch OFF.
2. Remove EVAP control system pressure sensor with its harness connector.
Always replace O-ring with a new one.
3. Install a vacuum pump to EVAP control system pressure sensor.
4. Turn ignition switch ON and check output voltage between ECM harness connector terminals under the following conditions.






CAUTION:
- Always calibrate the vacuum pump gauge when using it.
- Never apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or pressure over 101.3 kPa (1.033 kg/cm2, 14.69 psi).
Is the inspection result normal?
YES - INSPECTION END
NO - Replace EVAP control system pressure sensor.