my 012 xf is not starting. i suspect it is a communication problem with smart key. we tried programing key and still wont start. the dash lights come on air cond doors open and dash says ignition on , any guidance would be appreciated

 

I don't think you can put the ignition on without it communicating with the smart key. So if you press the power button and vents open / ignition comes on then I believe the key is communicating fine. (Someone with a 2012 model can confirm).

Have you tried pushing the brake pedal hard / stamping on it when you press the start button? Sometimes it can be hard to trigger that brake sensor

 

Duplicate post. As mentioned, have you verified that the brake application switch is operating?