LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Scion >> 2004 >> xA Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnosis >> DTC P0451, DTC P0452, DTC P0453: Evaporative Emission Control System Pressure Sensor/Switch >> Circuit Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit Description

The vapor pressure sensor, VSV for canister closed valve (CCV) and VSV for pressure switching valve are used to detect abnormalities in the evaporative emission control system.

The ECM decides whether there is an abnormality in the evaporative emission control system based on the vapor pressure sensor signal.

Fig 1: Evaporative Emission Control System Pressure Sensor/Switch Range Circuit Description
G03367181Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DTC P0453

DTC No. DTC Detection Condition Trouble Area
P0451 Vapor Pressure Sensor Output Changes Extremely Under Conditions:
Vehicle Speed: 0 mph (0km/h) And The Engine Speed: Idling Or Vapor Pressure Sensor Output Stuck 5 Min After Engine Start. (2 Trip Detection Logic)
  • Open Or Short In Vapor Pressure Sensor Circuit
  • Vapor Pressure Sensor
  • ECM
P0452 Vapor Pressure Sensor Output Remains Less Than Specific Value:
(2 Trip Detection Logic)
P0453 Vapor Pressure Sensor Output Remains More Than Specific Value:
(2 Trip Detection Logic)