The check engine light is not lighting up at all during a key in ON position.

last time my car Mazda familia sport 20 get flooded.i dried all parts in side and out and took two days to dry after checking every thing get dry, i started the engine.the engine started as usual and except the door lock crazy locking behavior which resolved by it self later otherwise every thing was ok. After driving almost one week,one sunny day 37 C and very humid day ,i get in to the car and started.it started normally and i begin to clean the windows while the engine is working.after 5 mints when i get in to the car i found out the engine was turned off by it self.i tried to start again it starts but get turnoff in seconds.finally when i check a dash board lights,i noticed the check engine light is not illuminating at all during turning the key to on or when the engine turn off.So what do you think i should do?do u think mu ECU is dead?