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Home >> Lexus >> 2003 >> RX 300 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0451: EVAP Pressure Sensor Range/Performance Fault >> Circuit Description

Circuit Description

Vapor pressure sensor, canister closed valve Vacuum Switching Valve (VSV) and pressure switching valve VSV are used to detect faults in EVAP system. See Figure.

DTC P0450 is set if 10 seconds after engine starts, vapor pressure sensor reading stays unchanged. DTC P0451 is set if vapor pressure sensor output changes while vehicle is standing at idle and pressure switching valve VSV is off. Possible causes are:

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