You have a "Magneti Marelli" single point electronic injection version
When the engine just does not start, the first thing to check is whether the inertia switch has engaged (it engages automatically in the event of a collision or road accident and blocks the fuel pump).
Inerziale.jpg
InerzialeDettaglio.jpg
In this case, however, when you turn the key in the ignition, you do not hear the noise of the petrol pump at all.
However, when the "Key Code" light stays on, the problem is different.
KeyCode.jpg
It could be the faulty key or the "Key Code" transponder which must read the key code.
I guess you've tried, if you have one, to start it with another key.
Keys with transponders can be duplicated ... as long as they are not broken.
I would first try to go to a key duplicator shop, if they can read the KeyCode of yours most likely the problem is with the transponder.
If they can't read the KeyCode and you only have one key ... there's a problem!
Another test you can do is try to borrow a compatible control unit of a Panda that does not have the keycode or has the keycode scodified from a Fiat garage.
For example, I have this:
IAW_6F.SM.jpg
it is not perfectly programmed for our engine (176B2000) but it works and above all it does not have the keycode. In an emergency ... you always manage to get home.