We have a 308 2008 1.6 vti petrol. it hasn't been driven for a few months and lights, battery, dash, locking are all dead no sound when turning over, nothing at all.

I was wondering this seems like a battery dead problem.

So i was going to buy a 027 battery to give it a go.

I tried a charge of existing battery but that didnt do a thing, after charge the cars horn went off (expected) and battery even showed a spark when connecting the + but then fusebox was warm and still no lights/locks/dashboard.

Would warm fuse box indicate i put the cables back on to the fusebox that sits on top of the battery in the wrong order?

I dont have a multimeter so if i buy an 027 battery (think that is what it needs)

a) is it a straight swap?
b) do i need to register new battery with the car?


or should i try a jumpstart first?

Thanks