Bringing this thread back from the dead, but I finally got around to fixing my P2420 tonight. I had a broken wire on the pump module as well. In my case, it was the blue wire with the white trace. It broke right at the plug, so I opted to buy a new plug and 7 new wires. This gave me the option to extend the harness as well as giving me fresh wires that haven't been pulled tight and corroding for the last 10 years. And since pictures were requested...
As you can see, the broken wire is missing quite a bit of wire. It's astonishing that I haven't thrown this code much sooner.
Edit: I forgot to add the part numbers.
Plug- 90980-12380
Wires- 82998-24250
My '06 V8 took 7 wires, so my total cost to repair was just under $50. Much better than $700+ for a new charcoal canister.