Here was my problem, no heat control,
the cable was OK and the lever (on your left) was moving. If you
look carefully, you will see that the hole in the lever (green
arrow) as a special shape, normally the white plastic part (red
arrow) match the lever. Mine did not!!!
Just so you know, when broken, it is
possible to turn by hand the center screw, but the hick is that
it's a never-ending story (the valve will turn 360° over and over).
So to find the close section of the valve you need to turn this
one 1/10 of a turn, run the van and check if you still got heating,
stop, turn it again 1/10 until you find the close position of the
I was in the Nevada desert at 104°,
you can imagine the rest.