EVAP Control System Pressure Sensor For California

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR





Description





The EVAP control system pressure sensor detects pressure in the purge line. The sensor output voltage to the ECM increases as pressure increases.




DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
- GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and wait at least 40 seconds.

NOTE:
Do not depress accelerator pedal even slightly.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Go to EVAP Control System Pressure Sensor For California.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connection E9. Refer to Ground Inspection in Circuit Inspection.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace ground connection.
2.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR FOR WATER
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check sensor harness connector for water.

Water should not exist.

Is the inspection result normal?
YES - GO TO 3.
NO - Repair or replace harness connector.
3.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 8.
NO - GO TO 4.
4.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 5.
NO - Repair short to ground or short to power in harness or connectors.
5.CHECK COMPONENTS
Check the following.
- Crankshaft position sensor (POS) ( CKP Sensor (POS) For California.)
- Refrigerant pressure sensor ( Refrigerant Pressure Sensor For California.)
- Tumble control valve position sensor ( P2004.)
Is the inspection result normal?
YES - GO TO 6.
NO - Replace malfunctioning component.
6.CHECK APP SENSOR
APP Sensor For California.
Is the inspection result normal?
YES - GO TO 9.
NO - GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Removal And Installation.
- INSPECTION END
8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
EVAP Control System Pressure Sensor For California.
Is the inspection result normal?
YES - GO TO 9.
NO - Replace EVAP control system pressure sensor. Service and Repair.
9.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END




Component Inspection
1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Turn ignition switch OFF.
2. Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister. Service and Repair.
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 and ground under the following conditions.






CAUTION:
- Always calibrate the vacuum pump gauge when using it.
- Do not 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. Service and Repair.