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Fuel Tank Pressure Sensor: Testing and Inspection

FUEL TANK PRESSURE SENSOR INSPECTION

NOTE: The following vacuum and pressure values are indicated by relative pressure from atmospheric pressure.




1. Connect the Special Service Tools (Engine Signal Monitor) to the PCM.

CAUTION: Do not apply a vacuum or pressure outside of the specified limits. Doing so will damage the fuel tank pressure sensor.

2. Apply pressure then a vacuum to the fuel tank pressure sensor according to the following procedure.




3. Decrease the applied pressure from 6.7 kPa (2.0 in.Hg) to -6.7 kPa (-2.0 in.Hg) and verify that the PCM terminal 3A voltage decreases accordingly.

NOTE: The output voltage varies with the measuring condition.

Measuring condition
- Input voltage - 5 V
- Outside temperature - 25°C (77°F)
- Atmospheric pressure - 101.3 kPa (29.9 in.Hg)




4. If not as specified, perform the following inspection.




a. Harness continuity
- Between PCM terminal 30 and fuel tank pressure sensor terminal A
- Between PCM terminal 3A and fuel tank pressure sensor terminal B
- Between PCM terminal 3I and fuel tank pressure sensor terminal C

b. Terminal voltage
- Fuel tank pressure sensor terminal A voltage: Below 1.0 V (Constant)
- Fuel tank pressure sensor terminal C voltage: Approx. 5.0 V (Ignition switch ON)

5. If terminal voltage is correct and there is harness continuity, replace the fuel tank pressure sensor.