P0451

DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR





Component Description





The EVAP control system pressure sensor (1) detects pressure in the purge line. The sensor output voltage to the ECM increases as pressure increases.
- EVAP canister (2)
- EVAP canister vent control valve (3)









CONSULT-III Reference Value in Data Monitor Mode
Specification data are reference values.









On Board Diagnosis Logic









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.
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.
4. If 1st trip DTC is detected, go to SEE Diagnosis Procedure.




Diagnosis Procedure
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. POWER SUPPLY AND GROUND CIRCUIT.










OK or NG
OK - GO TO 2.
NG - Repair or replace ground connections.
2.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR FOR WATER





1. Disconnect EVAP control system pressure sensor (1) harness connector.
- EVAP canister (2)
- EVAP canister vent control valve (3)
2. Check sensor harness connector for water.





OK or NG
OK - GO TO 3.
NG - Repair or replace harness connector.
3.CHECK COMPONENTS POWER SUPPLY
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 COMPONENTS
Check the following.
- Refrigerant pressure sensor ( Magnet Clutch Circuit (If Equipped).)
- Crankshaft position sensor (POS) ( P0335.)
OK or NG
OK - GO TO 5.
NG - Replace malfunctioning components.
5.CHECK APP SENSOR
P2122.
OK or NG
OK - GO TO 7.
NG - GO TO 6.
6.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform Accelerator Pedal Released Position Learning.
3. Perform Throttle Valve Closed Position Learning.
4. Perform Idle Air Volume Learning.
- INSPECTION END
7.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
SEE Component Inspection.
OK or NG
OK - GO TO 8.
NG - Replace EVAP control system pressure sensor.
8.CHECK INTERMITTENT INCIDENT
Trouble Diagnosis For Intermittent Incident Trouble Diagnosis For Intermittent Incident.
For wiring diagram, P0452.
- INSPECTION END




Component Inspection

EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister.
Always replace O-ring with a new one.
2. Install a vacuum pump to EVAP control system pressure sensor.





3. Turn ignition switch ON and check output voltage between ECM terminal 42 (EVAP control system pressure sensor signal) and ground under the following conditions.






CAUTION:
- Always calibrate the vacuum pump gauge when using it.
- Do not apply below -93.3 kPa (-700 mmHg, -27.56 inHg) or pressure over 101.3 kPa (760 mmHg, 29.92 inHg).
4. If NG, replace EVAP control system pressure sensor.