Suzuki XL7 2007 Service Manual page 231

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.
FTP Sensor Signal
Voltage
High, Approximately 1.5
Volts or More
Low, Approximately 1.5
Volts or Less
Conditions for Running the DTC
• Before the engine control module (ECM) can report
DTC P0496 failed, DTCs P0451, P0452, and P0453
must run and pass.
• DTCs P0100, P0101, P0102, P0103, P0111, P0112,
P0113, P116, P0117, P0118, P0119, P0125, P0443,
P0446, P0449, P0451, P0452, P0453, P0458, P0459,
P0496, P0498, P0499, P0560, P0562, P0563, P0721,
P0722, P2122, P2123, P2127, P2128, P2138, P2227,
P2228, and P2229 are not set.
• The fuel system is in closed loop.
• The engine run time is more than 16 minutes or the
long term fuel trim is stable.
• The vehicle speed sensor (VSS) is less than 3 km/h (2
mph).
• The engine is idling.
• The ignition voltage is between 10-18 volts.
• The FTP is between -18.7 to +7.5 mm Hg (-10.0 to
+4.0 in H2O).
• The ambient air temperature is between 2-32°C (36-
90°F).
• The start-up engine coolant temperature (ECT) is
within 10°C (18°F) of ambient air temperature
• The fuel tank level is between 12-88 percent.
• The volumetric efficiency is less than 35 percent.
• The barometric pressure (BARO) is more than 68
kPa.
• The above conditions are met for more than 4
seconds.
• DTC P0496 will attempt to run up to 10 times or the
test completes successfully once per ignition cycle.
Conditions for Setting the DTC
• The control module detects vacuum during a non-
purge condition.
• The condition exists for more than 4 seconds or for a
cumulative of 50 seconds.
Fuel Tank Pressure
Negative Pressure/
Vacuum
Positive Pressure
Engine General Information and Diagnosis:
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"
Description and Operation
"Evaporative Emission Control System Description: "
DTC Type Reference
"Powertrain Diagnostic Trouble Code (DTC) Type
Definitions"
Scan Tool Reference
• "Scan Tool Data List - Engine Controls - 3.6L (LY7)"
• "Scan Tool Data Definitions - Engine Controls - 3.6L
(LY7)"
• "Scan Tool Output Controls - Engine Controls - 3.6L
(LY7)"
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 inches H2O
with a scan tool.
6. Verify the scan tool FTP sensor H2O parameter is −
0.5 to +0.5 inches H2O.
➢ If the FTP sensor in H2O parameter is greater than
the specified range, 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 FTP sensor is −0.5 to +0.5 inches H2O.
➢ If the FTP sensor parameter is greater than the
specified range, replace the FTP sensor.
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