My most recent Witi installation was in an MDC Forbes 13ft caravan. As you can see from the photos the ideal location was the fridge compartment with the activation light on the front of the van.
The process always begins in the shed with the soldering – cutting a length of trailer cable, locating all of the main wires and soldering them into place with heatshrink for further protection.
From there we used rivnuts to secure the WiTi unit to the steel panel separating fridge compartment and van before running the cables out to the trailer wiring, the horn, light and battery.
The PIR sensor was left in a cupboard for the client to locate wherever they chose and the bluetooth intrusion alarm was fixed to the door. Note – if you DIY then the two components need to be within at least 1.4cm of each other to activate.