I am assuming is doesn't have a battery fitted in van so it may rely on the fuse at 5/7 pin connector to car for 12v.

There may be a differing wiring from car to 12v lights - you will need to trace wiring from light/s back to pin/socket plug with a test light or meter. Although there is an Australian standard, not all manufacturers and caravan owners follow the standards. Note power may only be activated when ignition on or on accessories.

thanks i'll try that you would there would be sum sort of fuse switch.

Peter,
Hi, yes I would assume there was a fuse (or two) & switch somewhere, bearing in mind Possum3's last statement (but I would hope that you don't have to leave a key in the ignition switch).
I'd be inclined to start at the car socket - to make things easier have a mate/partner to assist you if using a meter/test light plus a length of wire in case the leads are too short. It's not an easy job.

Without making life hard for you, check every switch you can find. They might not be on the wall, perhaps under a shelf & if one doesn't work, find out why.

One other option - ask a caravan repairer/auto electrician - they may know this van.

Most of those older vans with no power source of their own have no fuses. They rely on the power source (car) to have the fuses.

thanks everyone will have another go at it cools down to today 43c in the shade.

Bit cooler its freezing at 22* lol
I would fit a 10 - 30 amp circuit breaker depending on wire size ? The breaker can be quite high rated as it will trip
fast before wire damage ., Even thermal
Self. closing type . That way Mrs or those who have no experience dont have to reset breaker ., Chances are the wire size is minimal ?

my experience with older vans that had no battery all relied on the car fuses for protection. Try the seven pin socket on the car and see if there is a constant active there for (AUX) power, usually a constant supply. Some cars use the same pin position for wiring the reversing lights through instead. from memory pin 2..... and Mr Google seems to agree..... Next you need to open the plug on the van and see if there is a wire to match your power supply (pin 2).... leave it exposed and plugged in to the car, a test light will show you if there is a circuit. If the lights still dont work you will need to chase where the 12 volt wires go, if the stop turn park lights work on the van then that shows the circuit should be earthed, but it would not hurt to see if you can find the earth wire on the caravan and connect it direct to the earth wire on your car socket, often the earth is just hooked to the caravan with a screw to the chassis underneath where rust dirt corrosion all quickly make it unreliable, where as the lights might (usually dont) have an earth back to the plug.

After that you will need to follow the active wire into the van, test at where you can with the test light and see where the break/fuse/switch is.

Good luck.

Sarge.

thanks everyone have taken everything board time to redo all the 12 volt wiring ond go solar and battery.