LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2003 >> Prius >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Self Diagnostics >> Diagnostic Tests >> DTC P0450: EVAP Emission Control System Pressure Sensor Malfunction Or P0451: EVAP Emission Control System Pressure Sensor Range/Performance >> Diagnosis & Repair
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis & Repair

NOTE: Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected. When ENGINE RUN TIME in freeze frame data is less than 200 seconds, check EVAP VSV, charcoal canister and vapor pressure sensor.

For diagnosis and repair procedure, see Fig 1.

For EVAP system circuit wiring diagram, see Figure. For component locations, see Figure.

For ECM location, see Figure. For ECM connector terminal view, see Figure.

For removal and installation of components, see REMOVAL & INSTALLATION - 4-CYLINDER article.

Fig 1: DTCs P0450 & P0451 Diagnostic Procedure
G00249331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002