P0451

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 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 - Go to P0451.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connection M95. 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 CIRCUIT
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) (Refer to P0335.)
- Camshaft position sensor (PHASE) (bank 2) (Refer to P0340.)
- Exhaust valve timing control position sensor (bank 2) (Refer to P1078.)
- Battery current sensor (Refer to P1550.)
- Refrigerant pressure sensor (Refer to Diagnosis Procedure.)
Is the inspection result normal?
YES - GO TO 6.
NO - Replace malfunctioning component.
6.CHECK APP SENSOR
Refer to P2122.
Is the inspection result normal?
YES - GO TO 9.
NO - GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly
2. Go to P2122.
- INSPECTION END
8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to P0451.
Is the inspection result normal?
YES - GO TO 9.
NO - Replace EVAP control system pressure sensor.
9.CHECK INTERMITTENT INCIDENT
Refer to 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.
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.
- 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