Just put engine back in, solid immobiliser light

[Fraser.mac182]

Just dropped the engine back in my 182 after having it out todo belts and other bits and bobs. Went to start but wont even crank over. Ive checked and cleaned all earths and even created additional ones using jumpleads. (From earth on battery too chassis ect). Ive tried the key resets ect but nothing is working. The engine has been out for about 6 months. Is there anything obvious i have missed? Any help appreciated

Excuse my potato cam lol

 

[botfch]

Wiring fault somewhere also check the relays for water/corrosion.