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Fuel Tank Pressure Sensor: Testing and Inspection

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




1. Connect the SSTs (NGS) to the data link connector-2.
2. Select the "PID/DATA MONITOR AND RECORD" function on the NGS display.
3. Select "FTP V" on the NGS display and press START. The NGS measures and shows the voltage.
4. Turn the ignition switch to ON.

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




5. Apply pressure then a vacuum to the fuel tank pressure sensor according to the following procedure.
6. Decrease the applied pressure from +6.66 kPa {+50 mmHg, +1.97 in.Hg} to -6.66 kPa {-50 mmHg, -1.97 in.Hg} and verify that the "FTP V" voltage decreases accordingly.

Reference data

NOTE: The output voltage varies with the measuring condition.

Measuring condition




- Input voltage: 5.0 V
- Atmospheric pressure: 101.3 kPa {760 mmHg, 29.9 in.Hg}
- Outside temperature: 30 - 100° C {86 - 212° F}

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




1. Harness continuity
- Between PCM terminal 3U and fuel tank pressure sensor terminal A
- Between PCM terminal 3AB and fuel tank pressure sensor terminal B
- Between PCM terminal 3A and fuel tank pressure sensor terminal C

2. Terminal voltage
- Fuel tank pressure sensor terminal B voltage:
Ground (Below 1.0 V)
- Fuel tank pressure sensor terminal C voltage:
Constant voltage (4.5 - 5.5 V)

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