Circuit Description

2004 Oldsmobile Bravada AWDSECTION Circuit Description
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix, 2003 Chevrolet Malibu, and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

An ignition voltage is supplied to the Evaporative Emission (EVAP) canister vent valve. The Powertrain Control Module (PCM) grounds the EVAP canister vent valve control circuit to close the valve by means of an internal switch called a driver. The scan tool displays the commanded state of the EVAP canister vent valve as ON or OFF. The PCM monitors the status of the driver. If the PCM detects an incorrect voltage for the commanded state of the driver, 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 vent valve. See PCM TO EVAP CANISTER VENT VALVE RELATIONSHIP  table.

PCM TO EVAP CANISTER VENT VALVE RELATIONSHIP

PCM Command EVAP Canister Vent Valve Position
ON CLOSED
OFF OPEN
RENDER: 1.0x

NO RELATED

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • Brakes feel soft, pull hard to one side, or make grinding noises.
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