Hi all im new to all of this and im in need of help without hopefully spending money ive not really got.

My car is a 2011 1.6 focus sport 105bhp

I THINK i left my interior lights on last week when i parked my car up at home, 2 days later when i got into the car i realised it was dead,  no power for central locking or anything... i got some jump leads the following day and like a numpty i connected the wrong way round allthough i never actually started either car as i realised after about 5 seconds but the car that was charged already had a little smoke from battery.

I got some better jump leads and i charged the battery a bit and all the electrics worked fine... but the car wouldnt start, a horrid alarm noise goes of and it say engine malfunction on the screen, i spoke to a mechanic friend who bought his diagnostics machine to my house but he couldnt gey it to communicate, hes told me to get the car to his garage and he will strip it down but this sounds expensive, im hoping the the ecu (no idea what that actually is but told not much change from £1000) 

Any ideas that anybody could possibly think it could also be... is there a fuse that could blow before the ecu?  

Many thanks 

Phill

try charging the battery on the bench (with leads fitted corectly) until at least theres enough charge to turn over the motor and start it and if it starts you know the ecu is ok and what lights come on the dash , also when your mate has kindly offered to strip it down for you what exactly is he offering to strip down as personally i regard stripping a car down because of a flat battery a bit ott