Circuit Description

2004 Oldsmobile Bravada AWDSECTION Circuit Description
WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.

This DTC tests the Evaporative Emission (EVAP) system for a restricted or blocked EVAP vent path. The control module commands the EVAP canister purge solenoid Open and the EVAP canister vent solenoid Closed. This allows vacuum to be applied to the EVAP system. Once a calibrated vacuum level has been reached, the control module commands the EVAP canister purge solenoid Closed and the EVAP canister vent solenoid Open. The control module monitors the Fuel Tank Pressure (FTP) sensor for a decrease in vacuum. If the vacuum does not decrease to about zero inches H2O in a calibrated 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 valves. See EVAP CANISTER PURGE VALVE-TO-VENT VALVE COMMAND RELATIONSHIP  table.

EVAP CANISTER PURGE VALVE-TO-VENT VALVE COMMAND RELATIONSHIP

Control Module Command EVAP Canister Purge Valve EVAP Canister Vent Valve
ON Open Closed
OFF Closed Open
RENDER: 1.0x

NO RELATED

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