Auto not working properly on climate control

[GrahamS]

It was working fine and now what ever the weather, coolant/interior/exterior temp. I press auto and it just sits on 1 bar fan.

Everything else is working fine and the windscreen demist is still a hurricane.

 

[AlexW]

Ideally wants plugging in with a decent machine as you can see what temp it thinks it is, if it's too cold it won't increase the fan speed.