I replaced the batteries for the keyless entry FOB ( not advanced) for my 2008 CX9. They had been dead for 2 weeks but the key still worked perfectly.
Once I replaced the batteries, the FOB worked but I am not able to start the car as it seems the ignition has been disabled. Everything else works.
It was mentioned that the car needs to be taken to Mazda to have the immobilizer reset as there must be some problem with it now-- however, that seems unlikely as 20 minutes prior to replacing the battery, the car worked perfectly with just the key.
Any suggestions as to how to reset the immobilizer?
Thanks

 

Do you have a spare key?

 

No- this is the only key.