OK before everyone tells me to reprogram the key fob, I have. Both of them.

I can happily open and closed the car this both fobs and the engine will turn over (crank) but it will not start.

I am assuming that the immobiliser is active, all I have done is replace the cars battery that finally gave up on me.

I have a BlueDriver OBD2 diagnostic scan tool which tell me there are no faults but little else without the engine running. I have however cranked the engine and noted the RPM goes up to 420 ish so I assume the timing sensor is working.

Is there something else that I should be doing to reset the immobiliser?

Any help would be greatly appreciated. Thanks.