P2407 Evap code on '07 XC70

[dontfeedthevolvo]

This morning after going to the store, I started my car to be greeted with a CEL. Code is P2407- "Evaporative emission system leak detection pump sense circuit, intermittent/erratic"
My gas tank was at 1/2 a tank, and i'm certain the gas cap was turned to (several) clicks last time I fueled up. Mileage is 149000 miles.

Anyone have any experience diagnosing this code?

(EDIT) Its an '06, not '07

[Astro14]

Your car has a leak detection pump. It’s detected a leak. You’re going to have to smoke the evap system to determine where it’s leaking. VIDA could walk you through the tests. I haven’t had to do this (yet) but a common failure is the “J hose” under the back seat, that runs over the gas tank. Not easy to get to, some Googling will show you what I mean. Still, while that’s common, it doesn’t mean that’s what is wrong with yours, so do the smoke check and troubleshoot it completely before firing up the parts cannon...

[dontfeedthevolvo]

Thank you, i'll get that done