FBH Controller (GSM) is a remote control and monitoring module for the Webasto fuel-burning auxiliary heater used on TDV6 diesel applications. It allows the heater to be started and stopped remotely so the cabin and engine can be pre-warmed in cold conditions without approaching the vehicle. The controller interfaces with the fuel-burning heater and is triggered either through the vehicle's key fob follow-me-home headlamp function or by SMS text command, which requires an active SIM card to be fitted. Alongside heater control it provides SMS-based GPS tracking with location links, an external temperature sensor with configurable low and high temperature alerts, automatic engine-start detection, automatic heater shutdown when the engine starts, and automatic shutdown on low battery voltage. The harness is wired primarily for right-hand-drive installations; on left-hand-drive vehicles the 12V battery lead must be extended to reach the battery.