The fuel tank pressure sensor measures the pressure changes within the EVAP system. The sensor signal is monitored for rationality as well as electronic functionality. Electronic functionality is monitored continuously. The pressure signal may be incorrect due to an open or a shorted circuit. The signal voltage is limited by a minimum and maximum value. If the sensor signal remains below the calibrated low value for longer than 3 seconds, the code will set.

DTC P0452 will set if fuel tank pressure sensor signal value is less than -281 kPa when:

Condition exists for longer than 3 seconds

P0452 is a (type B) DTC.

To locate an intermittent problem, use the scan tool to monitor fuel tank pressure with ignition On.

Wiggling wires while monitoring fuel tank pressure may locate the area where a short to ground or open exists.

The signal voltage with the fuel cap Off should read between 2.35 - 2.85 volts, which represents atmospheric pressure or 0 inches of vacuum.