P0450

Wiring Diagram:

CIRCUIT DESCRIPTION
The sensor is installed on the fuel tank.

It senses the fuel vapor pressure in the fuel tank as compared with barometric pressure and converts it into voltage signal.

ECM (PCM) uses this signal as one of the signals to detect the EVAP system malfunction.

DTC Detecting Condition And Trouble Area:

DTC CONFIRMATION PROCEDURE

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and a tester, on a level road.

NOTE: Check to make sure that following condition is satisfied when using this "DTC CONFIRMATION PROCEDURE."
- Intake air temp.: -8 °C - 40 °C (18 - 104 °F)
- Engine coolant temp.: -8 - 110 °C (18 - 230 °F)
- Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)

1. Connect scan tool to DLC with ignition switch OFF.
2. Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and warm up engine completely.
3. Increase vehicle speed to 50 - 60 km/h (30 - 40 mph).
4. keep driving above vehicle speed for 2 min.
5. Stop vehicle and check pending DTC by using scan tool.

Step 1 - 7:

TROUBLESHOOTING


WARNING: This work must be performed in a well ventilated area and away from any open flames such as gas water.

FUEL TANK PRESSURE SENSOR CHECK
1. Remove fuel tank pressure sensor from fuel tank.
2. Check sensor air vent hole and pressure passage for clog. Clean if clogged.




3. Arrange 3 new 1.5 V batteries in series (check that total voltage is 4.5 - 5.0 V) and connect its positive terminal to Vin" terminal of sensor and negative terminal to "Ground" terminal. Then check voltage between "Vout" and "Ground".

Also, check if voltage reduces when vacuum is applied up to 6.6 kPa (50 mmHg) by using vacuum pump and if it increases when positive pressure is applied up to 6.6 kPa (50 mmHg) by using hand pump.

If measured voltage doesn't show such characteristic as shown in the figure, replace.

CAUTION:
- As connection to wrong terminal will cause damage to tank pressure sensor, make absolutely sure to connect properly as shown in the figure.
- Do not apply pressure higher than 98 kPa (742 mmHg) to tank pressure sensor by hand pump. Applying excessive pressure will break it.