Circuit/System Description
WARNING: This page is about a different variant/trim than selected.
The fuel tank pressure sensor measures the pressure or vacuum in the evaporative emission (EVAP) system. The engine control module (ECM) supplies a 5 V reference and a low reference circuit to the fuel tank pressure sensor. The fuel tank pressure sensor signal voltage varies depending on EVAP system pressure or vacuum.
The following tables illustrate relationship examples between the fuel tank pressure sensor and the ON and OFF states and the OPEN or CLOSED states of the EVAP components.
Fuel Tank Pressure Relationship
| Fuel Tank Pressure | Fuel Tank Pressure in. H2O/PSI | Fuel Tank Pressure Signal Voltage |
|---|---|---|
| Pressure | Positive Value, 14.9 in H2O / 0.54 PSI | High, 4.73 V |
| No Pressure | Near Zero, 0 in H2O / 0.001 PSI | 2.6 V |
| Vacuum | Negative Value, - 2.37 in H2O / - 0.08 PSI | Low, 2.3 V |
Fuel Tank Pressure to EVAP Leak Detection Pump Assembly Relationship
| Fuel Tank Pressure | Fuel Tank Pressure Sensor | EVAP Leak Detection Pump Switch Valve | EVAP Leak Detection Pump Pressure |
|---|---|---|---|
| Pressure or Vacuum | Positive or Negative Value | Vent | 100 kPa (14.50 PSI)* |
| Vacuum | Negative Value -1 kPa (0.15 PSI) | Pump/Not Venting | 99 kPa (14.36 PSI)** |
| Pressure | Positive Value -3 kPa (0.44 PSI) | Pump/Not Venting | 103 kPa (14.94 PSI)** |
| *Equivalent to barometric pressure reading. **The values are examples only. Your readings may vary from this depending on the pressure or vacuum in the system and barometric pressure. |
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