Rear window demister issues!

[chrisgreen]

Hey guys - can’t work out if my rear window demister is intermittent or just really slow at clearing condensation on the inside of the car. It works sometimes but seems to clear the outside of ice pretty quickly in the morning (although again this might just be intermittent).

Any ideas?! I’ve checked fuses and visibly look good.

 

[chrisgreen]

So mine only seems to work when the engine is running- if I turn on the demister before engine is on it doesn’t work. ( but light comes on). Even if I press the button and start the car it doesn’t work - I have to start engine then press button. Is this normal?

 

[Scooba_Steve]

Not sure if that's by design though i wouldn't be surprised. I wouldn't want such a high current item on without the engine running.