Engel wires

Not sure what colour wire is pos or neg, but just check the continuity with a multi meter and you will find out.

Cheers

If you unscrew the the socket type plug on the lead, the wire going to the centre pin is the pos wire.

Even though my fridge is an earlier model, I would have thought the Engel lead is standard.
However, my lead has a twin figure 8 cable with two grey wires on the plug end, one with a red stripe on it, which is the active wire.

Are you changing the plug over to something else?
All connections on my lead are moulded plastic and cannot be re-terminated.
I cut the Engel plug off and replaced it with a Merit plug to suit my standardised method of 12 volt connections.

White is pos. Black is earth.
The White pos wire sits under the white stripe on the outside of the lead.