P0496
DTC P0496
DTC Descriptor
DTC P0496
- Evaporative Emissions (EVAP) System Continuous Purge Flow.
Circuit Description
This DTC tests for continuous intake manifold vacuum flow to the Evaporative Emission (EVAP) System. The control module seals the EVAP system by commanding the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Closed. The control module monitors the fuel tank pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is more than a predetermined value within a predetermined time, this DTC sets.
Diagnostic Fault Information
Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Conditions for Running the DTC
* DTCs P0106, P0107, P0108, P112, P0113, P0117, P0118, P0122, P0123, P0131, P0132, P0133, P0134, P0137, P0138, P0140, P0141, P0201, P0202, P0203, P0204, P0402, P0404, P0405, P0406, P042E, P0452, P0453, P0458, P0459, P0462, P0463, P0502, P2195, and P2196 are not set.
* The ignition 1 voltage is between 11-16 volts.
* The barometric pressure (BARO) is more than 72 kPa.
* The start-up IAT minus the startup ECT is less than 12°C (53°F).
* The start-up ECT minus startup IAT is less than 50°C (122°F).
* The start-up ECT and IAT is between -5° C (41°F) and 40°C (104°).
* The start-up IAT is 3°C (37°F) less than the actual IAT.
* Purge start time is less than 360 seconds.
* Engine Run Time is more than 1 second and less than 120 seconds.
* DTC P0496 runs once an ignition cycle when the above conditions are met.
Conditions for Setting the DTC
The FTP sensor indicates vacuum during a non-purge condition.
Action Taken When the DTC Sets
DTC P0496 is a Type A/B DTC.
Conditions for Clearing the DTC
DTC P0496 is a Type A/B DTC.
Diagnostic Aids
* Observe the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition occurs that caused the DTC to set. This may assist in diagnosing the condition.
* The EVAP system tests run when engine is first started and meets The Conditions for Running the DTC. An intermittent condition could be caused by an improperly installed or damaged EVAP canister purge solenoid valve , or by a temporary blockage or restriction in the EVAP canister purge solenoid valve.
Reference Information
Schematic Reference
Engine Controls Schematics Electrical Diagrams
DTC Type Reference
Diagnostic Trouble Code (DTC) Type Definitions Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
* Scan Tool Data List Scan Tool Data List
* Scan Tool Data Definitions Scan Tool Data Definitions
* Scan Tool Output Controls Scan Tool Output Controls
Circuit/System Testing
1. Disconnect the EVAP purge solenoid valve electrical harness connector.
2. Start the engine.
3. Command the EVAP vent closed.
4. Increase the engine speed to 1,200-1,500 RPM.
5. Observe the fuel tank pressure sensor in H2O with a scan tool.
6. Verify the scan tool FTP sensor H2O parameter is -1 to +1 in H2O.
• If the FTP sensor in H2O parameter is greater then -1 to +1 in H2O replace the EVAP purge solenoid valve.
7. With the engine OFF and the ignition ON, disconnect the EVAP purge solenoid valve pipe.
8. Observe the FTP sensor in H2O parameter with a scan tool.
9. Verify the scan tool FTP sensor in H2O parameter is -1 to +1 in H2O.
• If the FTP sensor in H2O parameter is greater then -1 in H2O, replace the FTP sensor.
Repair Instructions
* Fuel Tank Pressure Sensor Replacement Service and Repair
* Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement Service and Repair
Repair Verification
1. Start the engine.
2. Command the EVAP vent solenoid closed with a scan tool.
3. Increase the engine idle to 1,200-1,500 RPM.
4. Observe the FTP sensor in H2O parameter with a scan tool.
5. Verify the scan tool FTP sensor in H2O parameter is -1 to +1 in H2O.
Clear the DTCs with a scan tool.