Fuel Tank Pressure Sensor: Testing and Inspection

1. Check sensor air vent hole and pressure passage for clog. Clean if clogged.
2. Check sensor O-ring for damage and deterioration. Replace as necessary.
3. Arrange 3 new 1.5 V batteries (2) 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 (3) 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 (1), 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.