security light flashing

IF you still have the original key .. Take it and this new key to a locksmith and get a key made that will work.. That's the only 'logical' way to solve this problem! .. The security system does not recognize the new key and engine is not going to start and run .. The BEST route to take is the one I suggested, don't try any other such BS as trying to by-pass the security system .. Have a locksmith make a 'couple of keys' that will work.