I have had my S on axle stands for the last 2 weeks. The rear wheels turn easily but the fronts are both stuck solid. I have had no issues with the brakes before hand as far as I know. Are my calipers seized or is this just normal?

 

There should be a bit of binding, only very light binding like, not enough to stop the wheel doing one rotation when you spin it.

Given what you said, I'd say there seized

 

Are you sure the pads have just not rusted onto the discs , the wheels having not moved for several weeks, was the car/discs wet when you put it up on stands ?

 

No, the discs and wheels were dry. Was able to turn both of them with a little effort after the first week but now both wheels locked and won't turn.

 

How do I unseize them if they are seized?

 

Buy new calipers.

 

Before I buy new/refurbed one's, how do I tell if they are seized? If I take them off and I can push the cylinders back in are they then not seized? Or is it not that simple?

 

Don't waste your time trying to fix them, you'll be on borrowed time. They'll only seize up again and leave you stranded somewhere. Nissin calipers are very bad quality and need servicing annually, if not then the sliders and pistons corrode and then they seize. Re-furbed calipers are about £100 each so just replace them and then service every year.

 

Has their been damp air where you live. And have the discs rusted at all?

 

These won't have magically seized just from the car being on axle stands. I'm betting rusting on the discs.

Put the front wheels back on and go for a drive. That should fix it, if not, then everything will be getting very hot.