fiat bravo ecu code box?

my fiat bravo 1.8 16 v n reg firstly has only 2 blue keys i dont have the red key.remote central locking does not work i dont have the 4 digit code. main problem is it wont srtart has no spark unless i remove disconnect the earth wire off battery then put it back on then it starts first go .mostly if i turn it off it wont start again but sometimes does unless i do the same battery disconnect and connect then it will start .when it does start the key code light flashes on and off constantly.all engine and body earths are fine checked all fuses ok.could it be the code box