Circuit Description
The fuel tank pressure (FTP) sensor measures the difference between the air pressure or vacuum in the Evaporative Emission (EVAP) System, and the outside air pressure. The engine control module (ECM) supplies the following circuits to the FTP sensor:
- A 5-volt reference circuit
- A low reference circuit
- A signal circuit
The FTP sensor signal circuit voltage varies depending on EVAP system pressure or vacuum. If the ECM detects that the FTP sensor signal voltage is less than 0.1 volt, DTC P0452 sets.
The following table illustrates the relationship between the FTP sensor signal voltage and the EVAP system pressure/vacuum.
DTC P0452
| FTP Sensor Signal Voltage | Fuel Tank Pressure |
|---|---|
| Low, Approximately 1.5 Volts or Less | Positive Pressure |
| High, Approximately 1.5 Volts or More | Negative Pressure/Vacuum |