How to connect these inexpensive and reliable wireless switches so you can turn your lights on and off from anywhere.
If this is your first 12v wiring project be sure to watch other video tutorials first and be sure you turn off the circuit you are working on and that every circuit in your system is protected with a fuse.

Think of the wireless switchboard device as having two separate parts: one part is the "brain", the brain needs power ie +ve and -ve from a battery. The brain part listens out for when you press the wireless switch and switches the switch part.

The other part is the switch. The switch sends +ve power to your lights. With the switch you have two options; default ON or default OFF, its as simple as that and does not really matter which one you use; as the remote switch will be able to switch ON and OFF anyway.

Since both the brain part and the switch part need +ve power, a jump cable is used to connect the two connections of the device that require +ve power supply (ie. the +VE and the COM terminals of the wireless switch)

The "brain" power should not come from the battery, it should come from your main light switch. Why? Because then the "brain" starts to work only when you have switched on your main light switch, and the light will come on as you would expect (each and every time you turn on the MAIN light switch). Thereafter you have the option of using the remote switch to turn off your lights (and on again etc). If you connect the brain directly to the battery it will always be on, and whether the lights turn on or off when you turn on the Main Switch will be dependent on the current state of the wireless switch (it could be in the OFF state).

("main light switch" = it is the switch that your van came with which supplies power to ALL of your lights in the ceiling)