key code light engine won't start?

this is how to resolve your issue, first the problem mainly occurs cause your using the red key, you should be using the blue key.
So what's happening is that everytime you use the red key, your opening up the ECU to reprogram it, so in time, you end up damaging the ECU, which is more than likely what has happened in your case.
What to do:
The MK 1 Punto uses 2 different types of boxes, a black box and a yellow box, so make sure you check before you replace it.
In order to to get your car started you have to change both the immobiliser and the ECU, as well as the barrel plus the blue key, go to a dismantler for them.
The reseason why you have to change everything is that the Immobilser has a uniqe code thats programed onto one chip on the ECU, this chip fixed, so you cant remove it and replace it with another one, wont work, hence the reason why the engine wont turn over.
hope this helps, also you know when the keycode is lost from the ECU, when you the turn the key to MAR, the keycode icon will blink in code, any problems or if you need futher help, let me know

NB
You can start your car for the time been like this, instead of turning to MAR first, turn your ignition all the way to start, you might have to try it a few times before it starts, so have patience, it doesnt make a difference if the keycode icon stays on or goes off and it wont damage your car in anyway....

Dave Morales
October 2011