DTC P0453: Evaporative Emission System Pressure Sensor/Switch High

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2011 Mercury Milan, 2011 Mercury Mariner, 2011 Mercury Grand Marquis, 2011 Lincoln Town Car, and 2011 Lincoln Navigator L. However, it is still accessible from the selected car via links, so may be relevant.

P0453 - EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/SWITCH HIGH

For Vehicles With NVLD Module
Description:	The natural vacuum leak detection (NVLD) module monitors the position of the NVLD module pressure switch. This DTC sets if the NVLD module pressure switch voltage is out of range high.
Possible Causes:	NVLD module GND circuit open Damaged NVLD module
Diagnostic Aids:
For All Others
Description:	The powertrain control module (PCM) monitors the evaporative emission (EVAP) control system fuel tank pressure (FTP) sensor input signal to the PCM. The test fails when the signal average jumps above a minimum allowable calibrated parameter.
Possible Causes:	Contamination internal to the FTP sensor connector FTP circuit open FTP circuit short to voltage FTPREF or VREF circuit short to voltage SIGRTN circuit open Damaged FTP sensor
Diagnostic Aids:	An FTP voltage PID reading greater than 4.85 volts with the ignition ON, engine OFF or with the ignition ON, engine running, indicates a concern is present.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
Fiesta	GO to PINPOINT TEST HZ .
All others	GO to PINPOINT TEST HX .