Lost a key !

Regrettably that is not possible you will need to get new keys cut to the lock or replace all the locks and get the keys coded to the vehicle security system

you must get a key fob and program it into the system good luck

The problem is with the factory security system; you'll need to reset the security code matching between the security system and the code on your keys that came with the new column.

Immobilizer seems to be active, same with your alarm. May be faulty, need to replace.

first most GM OEM systems will need to recognize the key first and foremost ,to do that you will need to roll window down on driver door,turn the key to the run position and with engine NOT running leave the key on for 10 minutes exactly ..then turn ignition off then try to start engine. if original system is working engine should start normally

This is from Ken on CarPros:
Here is the way to reset the security system.

https://www.2carpros.com/articles/how-to-reset-a-security-system

Here is the systems descriptions

There are 2 security system, namely anti-theft and immobilizer.

Here are the 2 systems.

DESCRIPTION & OPERATION
Anti-theft system is controlled by Body Control Module (BCM). BCM receives signals from hood switch, trunk switch, door switches and Local Control Modules (LCMs). There are 5 LCMs located throughout vehicle.

To set anti-theft system in armed mode, remove ignition key, close all doors, trunk and hood. Lock doors using key or remote controller. The SECURITY light will illuminate for 30 seconds, then flash in 2.4 second intervals, indicating system is in armed mode.

To cancel armed mode, unlock and open any door or trunk lid using key or remote controller. SECURITY light will flash every second, indicating system is disarmed.

Alarm will activate (horn sounds, headlights flash and starter circuit is disabled) if any of the following conditions occur while system is in armed mode:

Engine hood or trunk lid is opened using the hood or trunk lid release.
Door(s) is unlocked without key or remote controller.
Tampering with any door/trunk lid key cylinders.
To deactivate anti-theft system, unlock door or trunk using key or remote controller.

If it is the immobilizer that is preventing the engine from being started, ensure you have the correct key and the transponder is intact. Quite often keys are dropped and if it breaks open, the internals would scatter all over. When this occurs, there is a tendency for the transponder to be lost.

Please let us know happens so it will help others.

Best, Ken
I hope that helps you out!

Mazda does have a Electronic Code Keys on certain makes of there autos could be that your problem key is not turn on key only emergency key for when you have locked your key inside the truck you have to pull the papers togather for the truck and head on over to a mazda dealer they might have to make a new code key but without all the papers stateing you are the owner they can not help you do to auto theft the key wont be cheap either it could cost up to 150$ maybe more

Immobilizer system can be disarmed using 4 digit code from vehicle security card as detailed in owners handbook.

the key has lost it's code, there is a chip in the key that communicates with the security system that the correct key is in the ignition and that the vehicle is allowed to start.

if you have any other keys on your key ring remove these and try again.
if no start and light still flashes the computer will need reprogrammed to accept the key.
the dealer can do this in like 10 -15 minutes usually.

I've not heard of Brake Codes working on the 3rd or 4th generation Rolling Code Sidewinder Keys. There is simply no reason to, since a Honda Tech can simply access the Immobilizer System through the HDS (Honda Diagnostic System Laptop) with the Daily Access Security code providec by the Honda System. He can even reflash (reprogram) the ECM using this Daily Code.

In a case like this, normally Honda will have the Accord towed in and do a "All Keys Lost" reset with a new set of keys. This will also prevent your "Lost keys" from being used in the future by who ever may find them.

If you ever buy a used Honda at a Honda Dealership, most likely they also did a complete Key code reset just in case to protect you.