2009 Chevy Avalanche - P0449

Hello,
I’m working on a 2009 Chevy Avalanche with the old P0449 which every GM has. And what I have going on here is my main supply wire is at 12.2. And the control wire is also 12.2 which means that my solenoid is good (resistance in solenoid is around 20 ohms). After find thing that out I was hoping my wire is open somewhere but I did a continuity test and measured voltage at the pcm connector and it also was 12.2 volts. So now all the wires and solenoid is good. Does that mean I need a new pcm? Because when i get my scanner out and try to close it and open it back up voltage stays at 12.2v, when the pcm is supposed to ground the wire, and the solenoid doesn’t click. Also I bought this truck with this code and the guy told me that he replaced the solenoid. So he could’ve friend the pcm? 

Please someone help! Thank you!

Markorni, I moved your post out of its original location and into its own thread. More exposure and better help this way. 

So to be clear, if you command the EVAP vent solenoid closed (or 'not venting' in GM-ese) while watching pin 61 of connector X1 at the PCM, the voltage on your meter stays at 12V, correct? If so, the only other thing to check would be pin tension on #61. Someone may have spread it open doing some front probing.

As extra assurance, I'd also suggest measuring the current of the vent circuit with your multimeter. Key on, backprobe pin 61, set your meter to measure current, hook one lead to your backprobe and the other to ground. I'd expect about half an amp. If less, there's still a circuit problem. If more, there's still something wrong with the vent solenoid.

If you find no pin tension problems, and the vent solenoid circuit current is good, then it's PCM time! 

Thank you so much for your reply. Can you please let me know what amperage is too high and what’s too low. And is it possible for a pcm to go bad with everything else working absolutely perfect?

Personally, my upper and lower limits would be 1.0A and 250mA. There's no basis for that in service info, just my experience with GM vent solenoids.

Is it possible for the PCM to fail on its own? Sure! I'm just very suspicious when it's a failure prone circuit like the vent solenoid. 

Ok so after I did some wiggle nc around and checking the connection is started working. Than I came back In a couple hours and I got the check engine light on again and the same p0449. I checked voltage connections, wires, everything and again it’s not working. and I spent another hour or two wiggling, unplugging, plugging back in checking for pins not to be bent anywhere, like I did the whole process again and I can’t get it to work again