I just bought a 1997 CRV for my teenage daughters first car. The owner gave us several keys but no key fob remotes. I ordered a couple online and tried the programming instructions but they car is not going into programming mode. The locks never cycle. When manually locking the car, all the locks but the front passenger door work, that one has to be locked and unlocked manually for some reason. I tried different batteries in the key fobs but still no success. I know I followed the instructions carefully and tried multiple times. Any ideas as to what the issue is? He did remove the factory radio to replace it with a bluetooth one, I read in one thread that the factory radio may be needed for the key fobs to work? Either way, the car was never even entering programming mode as the locks would never cycle. Thanks.