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P0496



DTC P0496

Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Diagnostic System Check - Vehicle
Review Strategy Based Diagnosis for an overview of the diagnostic approach. Strategy Based Diagnosis
Diagnostic Procedure Instructions provides an overview of each diagnostic category. Diagnostic Procedure Instructions

DTC Descriptor
DTC P0496: Evaporative Emission System Flow During Non-Purge

Circuit/System Description
This DTC tests for undesired 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 OFF and the EVAP canister vent solenoid valve ON. 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. The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent solenoid valves.






Conditions for Running the DTC
DTCs P0107, P0108, P0112, P0113, P0117, P0118, P0125, P0128, P0442, P0443, P0446, P0449, P0452, P0453, P0445, P1106, P1107, P1111, P1112, P1114, P1115, P1516 are not set.
The ignition voltage is between 10-18 volts.
The barometric pressure (BARO) is more than 74 kPa.
The fuel level is between 15-85 percent.
The engine coolant temperature (ECT) is between 4-30°C (39-86°F).
The intake air temperature (IAT) is between 4-30°C (39-86°F).
The start-up ECT and IAT are within 9°C (16°F) of each other.
The vehicle speed sensor (VSS) is less than 121 km/h (75 mph).
The FTP sensor is less than -2.5 inches H2O at ignition ON.
DTC P0496 runs once per cold start for 96 seconds.

Conditions for Setting the DTC
The control module detects vacuum during a non-purge condition.

Action Taken When the DTC Sets
DTC P0496 is a Type B DTC.

Conditions for Clearing the MIL/DTC
DTC P0496 is a Type B DTC.

Reference Information

Schematic Reference
Engine Controls Schematics Electrical Diagrams
Evaporative Emissions Hose Routing Diagram Evaporative Emissions Hose Routing Diagram

Connector End View Reference
Component Connector End Views Connector Views

Electrical Information Reference
Circuit Testing Circuit Testing
Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
Troubleshooting with a Test Lamp Troubleshooting With A Test Lamp
Wiring Repairs Wiring Repairs

DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference
Control Module References for scan tool information Control Module References

Circuit/System Testing

1. Ignition ON, engine OFF, seal the EVAP system using the Purge/Seal function with a scan tool.

2. Start the engine.

3. Observe the fuel tank pressure sensor with a scan tool. The Fuel Tank Pressure Sensor parameter should be less than 1.7 volts after 90 seconds. If the Fuel Tank Pressure Sensor parameter is greater than the specified range, go to Circuit/System Testing.

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
Evaporative Emission Canister Purge Solenoid Valve Replacement. Service and Repair
Fuel Tank Pressure Sensor Replacement. Fuel Tank Pressure Sensor Replacement