Question edited for clarity.
Question moved from Motorcycles to model category.
You can't bypass vehicle alarm and security systems. They are there to stop exactly what you are trying to do. You have two computers, the ECM and BCM, plus the alarm module and a number of sensors protecting the vehicle from theft and unauthorized removal. You can't trick them because you can't reprogram them.
Either do a security system reset or find an auto electrician or locksmith / alarm installer. Cheaper than the dealership!
https://www.google.com/search?q=mobile+auto+electrician+near+me
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Question edited to add in 'year make model'.
Question moved to model category.
Jeff Armer is the Expert Auto electronics Expert on the site, but I found two ways to reset the Security System and Immobilizer.
https://www.google.com/search?q=2008+ford+fusion+security+reset
Insert the key into the driver's side door lock.
Turn the key once, but not all the way to unlock the door. Leave the key in this position for 40-60 seconds. ...
Do this again, but turn the key in the opposite direction.
Remove the key from the door, get into your Ford, and start the engine. The system should be reset.