I just googled "ignition on engine off trailer brake lights don't work" - first hit was this thread!
 
Don't go out in the wet in me shoes - the laces fall off! If I'd gone out in a thong in the winter cold - something much more personal might have snapped off!

No self respecting Kiwi would go out wearing a thong - must be an Aussie thing.
 
Stop and tail bulbs? Maybe fitted wrong way around? Or maybe just needs extra power from engine running I'll check mine next time I've got the trailer hooked up n see what it does..
 

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