P450 - Evaporative Emissoin Control System Pressure Sensor Malfunction
P451 - Evaporative Emissoin Control System Pressure Sensor Range/Performance
Circuit description
DTC Detecting Condition
DTC |
Detecting Condition |
Trouble Area |
P0450 |
10 seconds or less after engine starting condition vapor pressure sensor fixed value continues for fixed value or more: (2
trip detection logic) |
- Open or short in vapor pressure sensor circuit
- Vapor pressure sensor
- ECM
|
P0451 |
Vapor pressure sensor output extremely changes under conditions of (a) and (b): (2 trip detection logic)
- (a) Vehicle speed: 0 km/h (0 mph), Engine speed: idling and VSV for pressure switching valve is OFF
- (b) vapor pressure sensor value >= opening pressure valve of charcoal canister
|
- Open or short in vapor pressure sensor circuit
- Vapor pressure sensor
- ECM
|
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.
DTC P0450 or P0451 is recorded by the ECM when the vapor pressure sensor malfunction.
Wiring diagram
Steps
VSV for Canister Closed Valve: Testing and Inspection
Inspect VSV for Canister Closed valve (CCV).
1. Using an ohmmeter, check that there is continuity between the terminals.
Resistance: 25-30 Ohms at 20 C degrees (68 F degrees )
2. Using an ohmmeter, check that there is no continuity between each terminal and the body. If there is continuity, replace the VSV
3 .Check that air flows from ports A to B.
4. Apply battery positive voltage across the terminals
5. Check that air does not flow from ports A to B. If operation is not as specified, replace the VSV.