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Circuit/System Description

This DTC tests the evaporative emission (EVAP) system for a restricted or blocked EVAP vent path that would cause excess amounts of vacuum to be developed in the EVAP system. With the purge valve open and the canister vent valve open, if the EVAP system vacuum goes above a calibrated threshold, the test will fail.

FTP Sensor Signal Voltage Fuel Tank Pressure
1.5 V Atmospheric Pressure/BARO
Less than 1.5 V Positive Pressure
More than 1.5 V Negative Pressure/Vacuum
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