Extreme cold and battery

[Craigy]

I think you can connect the external 12v to the main connection in the fuse box to the right of the engine. This is where the mechanics attached the jump pack for me.

 

[jaapv]

There is a little lid in the boot hiding the battery terminal.

 

[littlescrote]

There is a little lid in the boot hiding the battery terminal.

yes, terminal (singular). the -ve.

if you need to access the +ve as well, for example to 'jump start', that's what the place under the bonnet is for.