Trailer Stability Program, or TSP, is an extension of the car safety system known as Electronic Stability Control, or ESC. It applies exclusively to trailers and caravans. It is designed as an extension to ESC and, on vehicles that have TSP, provided a vehicle specific tow bar wiring kit is used, it is automatically turned on whenever a trailer plug is connected to the vehicle’s towing socket. The system uses the information from the ESC sensors to monitor the movement of the towing combination and check for any “snaking” movements, and to control them before they become dangerous. A trailer or caravan may start to snake dangerously for several reasons. Manner of driving, crosswinds, speed, condition of the road surface and/or a badly laden caravan or trailer can cause problems. If any snaking starts, drivers may react by counter steering the vehicle or speeding up. Both of these are dangerous as they amplify the effect of the sway and may result in an accident.