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Hi Folks,
thought you might be interested in my lamp testing and 13 pin plug testing kit.

This only works if you have a leisure battery installed that charges from the tow vehicle electrics, most do nowadays.

It's simply a 13 pin socket screwed to a bit of wood with the 13 pins wired in to a 13 way terminal strip. Also need a short piece of wire.

Pin 9 should be permanently connected to the battery, so that is the supply used to test the lamps and electrical functions of the caravan.
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Pic 2 now has the caravan's 13 pin plug inserted in to the 13 pin socket. Pin 9 and pin 1 are shown connected which tests the left indicator. A quick look round the back and it's on therefore everything is good from the 13 pin plug through to the indicator lamp.
Other functions can also be tested for example pin 10 which should bring up the red indicator lamp in the fridge switch if you have that fitted. I also use pin 10 to power a normally off relay. When not powered (simulating disconnection from the tow vehicle) the awning light works. When powered up, the awning light is disabled but my rear facing dash cam is powered up.

Ray,

great project - thanks. This is now on my to-do list.

Can you expand on the relay/wiring etc for the rear dash-cam/awning light - thats a project I have been mulling over for some time.

I have been looking for a rear-view camera that can be readily moved from car to caravan - i.e. wireless

Thanks for any further info

Dave

Edit: PS and how do you get the battery 12v supply to pin 9?

Hi Dave,
last point first.
My 2007 Triton has factory fitted battery charging on the move so it comes with a Schaudt Booster. Pin 9 is connected to the booster and from there to the battery. Other tow car charging arrangements may be different but simply stick a voltmeter across pins 9 and 13 (earth) and see if you have 12Vdc.
If you don't have 12V on pin 9, you can have a trailing lead through the window to a convenient 12Vdc power socket in your van. Connect the 12V earth to pin 3 and then the +12V to any of the the pins to test in the same way. That's how I had mine arranged originally until it dawned on me that I already had 12V available at pin 9 without needing a trailing lead.

The first question is a little more complicated and remember it works on my BIP power pack ref: 30.65100.84. Yours may be different but you might be able to follow the same principle.
We have two requirements, to stop the awning light from working when connected to the tow car and also to provide power to a dash cam when connected to a tow car. Thus we need a way of knowing when we are connected. In my BIP there is a relay that operates the fridge on 12Vdc when connected to the tow car. This is powered from pin 10 of the 13 pin plug. So I took a supply from the fridge relay coil connection and used it to energise a change over relay. The common for the c/o relay comes from terminal 6 ( normally fused at 10amps ) on the BIP 12V distribution section which is spare. I removed the awning light supply from terminal 1 and connected it to the normally closed output of the new relay, thus when there was no power to fridge relay, the new relay would connect allowing power to the awning light. I then used the normally open contact of the new relay to power the dashcam which would only liven up when the new relay was powered up from the tow vehicle.
I'll knock up a sketch>>>>

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Ray,

that's really helpful, many thanks - I will investigate.. I had always assumed that my electrics had been set up to charge the battery whilst the tow-car was connected and engine running,

Thanks again. I'm sure your post will also be of interest to others

Dave