Join Date: May 2005
Location: Exiled in Surrey
My Motorhome: Rapido 7066DF
Thanked 269 Times in 220 Posts
There are no standards laid down for low voltage DC polarity in the EU and indeed I've found some odd colour combinations used on German and Dutch wires, they often like to use grey and light blue for instance.
In the case of "round post" battery terminals you can always identify the positive terminal because the "hole" in the middle is larger. It should be pysically impossible to get the negative connection to fit over the battery positive terminal.
With terminals that are flat with a bolt through you'll need to use a continuity meter to determine polarity, the wire that goes to the chassis will be the negative in most vehicles made since the 1970s (except possibly Volkswagen who ISTR still used a 6v system with a positive earth).
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