Help! Car is immobilised after d/c'ing battery?


I was doing a bit on work on the k12 the other day and I dc'd the battery to make a bit of space in the engine bay and left it off for about 30 mins or so while I fitted an after market radio.

After reconnecting it, I put the keys in the ignition and the car locked and re-opened itself (which i found weird) but after that the car would not start and the immobiliser light was flashing, even when it was unlocked.

The ignition comes on fine and as normal and the central locking works. All i had done was dc the battery, attempt to fit a thermostat (failed), fit an after market radio and unplug the trip/mpg cpu and thats it. I thought maybe the codes on my keys were wiped but they are still registered on the obd.

Nissan havent really give me an answer except to get an auto electrician out but i would like to avoid doing this.

So what are your thoughts?
When I changed the starter motor I had my Battery disconnected for a good 2/3 hours. And I've had no problems. Have you tried double checking the connections? How old is the battery?

I dc'd the battery and left it 30 mins before recon. and it worked fine. Infact, it even wiped the flashing airbag fault light :D

I also had a bluetooth obd onboard at the time with the torque pro app running but im not sure if it had anything to do with the fix.. but who knows, it could have :p