V50 Starting issues plus temp sensor gone mad

[walks]

I have a starting issue with my V50 2Lt D 2006 when you fully turn the key it takes 5 to 10 seconds before the engine turns over,I have removed the starter tested it and its fine,sometimes the message on the dash states imobilizor check manual also the temp sensor tell me its -20 outside when its actually 12deg this false reading makes the aircon haywire in the car
Any advice would be much appriciated,I have also changed the key fob batteries but still the same