I have 60,000 miles on my 2012 Express Van, 5.3 L, and it just started to show a P0449 code every time I start the truck. I clear it after start up and the "Check Engine Light" stays off until the next start up. I can't seam to find any information of the internet specific to troubleshooting a P0449 code on an Express van. Any input would be appreciated...

 

https://www.obd-codes.com/p0449

 

I had the same code on my 2007 2500. There was a break in the power wire that powers the EVAP system. As soon as I spliced the break area and plug it into the cannister system I heard the click. Problem solved.

 

I read one post on another board that the wiring should be tested. What was the location of the break?

 

I found the break about a foot and half from the switch. I located a diagram of the fuse box thats located in the engine compartment and confirmed that power was going to the switch and from there I just started testing about every 12 inches or so towards the unit and finally found a spot where there was no power and then tested back towards the fuse box and finally closed in on a small spot of discoloration on the wiring. I pinched it and it felt hollow and sure enough the wire was corroded into. So I just peeled off enough insulation to splice it back together, plugged the connector back into the unit and it clicked immediately. Problem solved.