[Newbimer]

It may be blocked up. You can take them apart, clean, lube and re-install, see what happens. You can bench test it as well with any 12V source.

 

[Newbimer]

You can check its operation. Warm up the car put your heat on high with max temp setting. Remove the electrical plug and connect a 12V external source to the valve. If you get heat, the valve if working, but your have no/low power supply to the valve plug.

 

[Newbimer]

The OAT is 19 degrees so the heater should be blowing hot air providing you have increased the setting above that. Set it to max with fan on high. If you don't have one yet, get an infrared laser thermometer so yo can just point at each hose to see what the actual temp is. That will allow you to work backwards to find the point where its really hot and follow it to where it cools down rapidly, the blockage/problem will be between those two points. You should also be able to determine if the blend air doors are opening when you see a temp change at the outlets.

 

[Newbimer]

You could try disconnecting the hoses and push in a hand snake, like this one for unclogging drains. Its small enough to get in there and flexible to make the turns. If you use one like the one in the image, send it in backwards, keep the large coil out so it won't get caught on anything. That will at least let you know if you have any internal blocked sections in the pipes/and or which pipe. It may even clear the blockage and restore your heat. Just do it nice ans slow, don't try to rush it, in either direction.

I don't see anywhere on the "Quick Reply" that allows me to upload a image. Selecting "Insert Image" only allows you to upload a url to an image. Just google "hand snake for drains". You only need the cheap Home Depot kind that's just the snake with the handle, but without a housing.