Land Rover LR3 (2006 4.4) Code Advice

[denver6161]

I recently started getting a check engine light on my 2006 LR3. Pulling the codes with the GAP tool shows a number of the common "phantom" codes as well as the one below:

• P2451-00 (AA) Evaporative emission control system switching valve stuck closed

I don't have a lot of experience dealing with some of the emission control systems on this truck. Could this be related to the fuel cap or should I be pulling the evaporative canister or something else? Just curious if there are any other resources out there that I could use to track down the issue. TIA!